Many people who use the Align 2 in 1 regulator that provides 6v to all the electronics, but they use a step down regulator for gyros/tail servos that do not support 6v. 

http://www.amainhobbies.com/product_info.php/products_id/18532/n/Align-51V-Two-Way-Step-Down-Voltage-Regulator

It is just a diode each on the forward and reverse paths that drops about 0.7v, with the resultant voltage just over 5 volts (instead of 4.8v).

Where you use the step-down depends whether both your gyro and tali servo are 4.8v rated...  if the gyro is 6v capable and the tail servo can only take 4.8v, then the step down goes between the gyro and the tail servo.  Otherwise it goes between the receiver and the gyro.

As I mentioned, that i am not too happy with the 1500mah nicad on my heli, I have decided to upgrade the RX batter to A123 6.6V 2200mAh pack. I have one of these packs from Enerland systems - http://hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=8249&Product_Name=A123_Systems_2300_6.6v_2S1P_Rx_pack_Lithium_ion

All my cyclic/collective servos and the Spartan gyro is compatible with the higher voltage, EXCEPT the rudder servo which is Futaba 9254 and uses 4.8V only.
Now, since I do not want to use a voltage regulator, plus the diode one is out of stock with rotor ), I am going to replace my rudder servo and use the Turnigy BLS980 Digital Brushless Heli Rudder Servo :
http://hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=9980&Product_Name=Turnigy_BLS980_Digital_Brushless_Heli_Rudder_Servo_3.1kg/.03sec/58g_

I have this in my stock, and going to replace that today.

Never new about this tail servo... please post your comments after flying it for some time. 

I see more and more Align DS650s (and some Futaba BLS251s) as tail servos amongst our friends these days.

This came up recently on HK website. I thought i would give it a try considering the good specs. Will post a review/experience after a few flights.

Well ok, I changed the NiCad to the A123 and swapped the trusty Futaba 9254 with a Turnigy BLS980 one.
I felt no difference. Turnigy is faster, and works flawlessly ( as of now ) .
I did have to reverse the settings but otherwise i can say it works great. Since the change I have done 5 flights so far and its held the tail like a rock and yet given me fast piros .

I am having a great time with the Raptor 50. Very stable and visible in the air.
One thing i wanted to know was, that everyone says NOT to do 3D with the woodies. What exactly does 3D constitute ?
Can i try to do a flip with wooden blade ? Or loops/rolls ( Since i am learning they may not be the smoothest ) . Can the woodies handle all of these  ?

How do you charge A123? Also some people were commenting that for the price of 76$ the servo should be atleast programmable.

My Tahmazo ( and most other chatrgers today ) Support Life. Charging is pretty much like Lipo, just different voltages.

About the servo, I didnt care if it was programmable, as i would have never bought the programmer.
Time will tell if it really was worth it or not .

Oh crap, i didnt know a123 was li fe 

 But why Li fe, why not Lipoly?

A123 battery voltage is 3.3V per cell and 2Cell pack is 6.6V and does not require a voltage regulator.
In my opinion thats a big advantage. Plus are safer.

Peak charge voltage -3.6v officially but can go up to 4.2 with little damage (but not regularly) for A123.
source = http://www.flyelectric.ukgateway.net/lithium-a123.htm

so 3.6 X 2 = 7.2, will not damage electronics soon in the long run?

Well if you use a 5Cell Nicad of 1.2V then please search and post  what the max/peak voltage can be.

Please dont get offended my friend. Well I never considered people using 5 NiCDs. When some one says RX NICD, for some reason only 4 cells come into my mind. Probably coz I have a 4 cell NICD holder with me. and I always use esc becs for helis I have as they are small Helis.

Hey buddy,
I wasnt offended. Just typed that message from my cell and couldnt really look up the exact voltages.

There are 2 types of Nicad Rx packs people use. 4Cell that has a 4.9V and 5Cell that has a 6V.
Majority of servos and nearly all rxs are capable of handling the 5Cell Nicad ie 6V

Now the peak charged voltage of NiCd is around 1.4V This makes the pack 7V . Now if the RX can tolerate 7V then why not 7.2V

That was all theoretical. I have had over 100 flights on my Javellin airplane, that has a A123 pack. So far no issues.

Good to know that RXs are that flexible. When I got into this hobby, I was scared to even give above 5V to the RX as the manual said 4.8 V.

Here's another video of my flying my Raptor 50 yesterday.
Did 3 tank full of flights yesterday and done another 3 today. Confidence level gone up a lot.
However with the kind of stability and visibility in air this offers, Mini Titan has taken a back seat.

Anwar, Rajesh,

I have a question here. Now that I am comfortable flying, I want to upgrade my Collective ( and perhaps Cyclic  ) servos.
Currently using the Hitec 5485 digital . which are the cheapest Karbonite ones.
Please suggest what you think would be the best servo i should be using , that would last me a long time.

Thanks
Gaurav

Being the Align fan boy I am, I would go with the Align DS610s . 

Seriously, I believe in what I see on practically every other recent heli on the field, and have only good things to say about these.  They are a bit noisy, but then who cares once the engine gets going !

People on the forums repeatedly mention that they are pretty much equal to the JR DS8717 (probably the best servo these days), but then 40% the price !

The Align DS620s which are a bit more speed with a bit less torque is another option.

you recommend this for collective as well as cyclic ?

People use them both as swash servos on Trex 600s and Trex 700s, doing hard 3D. Therefore I see no issues with either being used.  If you want the collective one to have more torque (since the Raptor is non CCPM), go with the DS610 for collective, and either for the cyclic. I think the DS620s are slightly cheaper than the DS610s.

Ok, and I presume, will have no problem using it with my Futaba servo ?
Anyone in India stocking these ? Or do i go the helipross route

I have used Futaba 9252 and Ace RC DS1213. DS610 beats them on specs/price. I'd try them if I were to build a heli now.

Only thing to watch out for would be if you are using a regulator. High torque and speed comes at the cost of higher current consumption. We need to consider the hot climate we have that reduces the headroom these regulators have. For example I decided against flying my last pack today considering how hot the ESC heat sink got just by sitting inside the car. I thought it was better to keep it inside the car between flights than leave it exposed to the sun. It didn't help. Two months back in colder climate it never used to get that hot even during a flight. But if they work in Anwar's desert it should work here just fine.

No suggestions from the Hitec camp ?

Best deal found so far : http://www.readyheli.com/
3 for $190

No personal experience, noticed the store on US forums... http://www.infinity-hobby.com/main/product_info.php?products_id=3464