I know there are so many different ecus and ways to tune the ls6 but i wanted to know what worked best for them

 

Id start with asking this in the tuning section!

https://ls1tech.com/forums/pcm-diagnostics-tuning-7/

But honestly your theread might just get locked. Theres no "best". Personally I like HPTuners cause its easy to use, constantly updated, and has a large user community to help you...

 

+1 on checking the the tuning section . efilive and hptuners are some if not the best . FAST makes a pricey system . many variables as far as what you are looking for .