Which B5 rules to use

I want to run a FT B5 game but with all the available B5 adaptations out
there I don't know which to use.

For those of you who have tried out the various variations, which is the
best?  I just would like to get a general idea of which one is most
popular
so I can learn that one instead of reading them all.

And in your answer please give a short reason why you like a particular
version.

Thanks in advance.

Will