With limited knowledge of electronics and programing I had question not leaving me alone..

which is better for multirotors and why ....BLHELI OR SIMONK

requesting experts and  more experienced members to share their views....  

Both are good. It depends on the user. The Simonk are like naza, pretty easy with less options whereas BLheli is like APM lots of options to tune to your taste. I think the esc has to have matching hardware to support BLheli.

thanks for the info ashimda....
any pros n cons for these ? ? ?

if you are not sure what to choose then go with simonk ...simple & easy to program 

thx h4xk3r5 ...
m already using simonk.....

this info is for my future project so want to know pros n cons about blheli 

Blheli has a lot of great features and is now getting better and better, and in my opinion, is much better than SimonK.
Go look up Oneshot and Active Braking and you would know.

I prefer simon k flashed escs as they are beginner friendly and reliable

SimonK are easy to go easy to use, Not many options to configure or program. Just calibrate the ESC (throttle) and you are good to go.

Where as BLHELI are the newest in the market and has a lot of promise. The reason why its being loved by many users, is that it provides a lot of options to configure or tune. So users who are advanced or know how to play with these values they like to use blheli instead of simonk. Where as first timers or guys who really want easy to use esc goes with SimonK

Could regenerative braking possible with any one of these ?

Yes, both BLHeli and SimonK have active braking. In BLHeli, it is called 'damped light' and needs to be be enabled in the GUI. In SimonK it is a combination of comp_pwm and motor_brake and needs to be enabled in the source and flashed to the ESC.

These techniques actually reduce flight times as they take up energy to actively slow the motor. However, I have seen some interesting test data at RCGroups that shows that active braking actually can cause reverse current spikes back into the battery (varies depending on the ESC). However, they only last a few milliseconds so this isn't exactly the 'regenerative braking' you are looking for ( I assume you mean recharging the LiPo while flying).

Take a look at the following posts:
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