I just went through this with my LS3 build. I ended up going with the 8-Rib kit from Eddie Motorsports.
http://www.eddiemotorsports.com/
I'm super happy with it, zero complaints on my end. I basically got it together then did Power Tour with the car. Not a single issue!
The kit went together really easily too, not too complicated or anything. They support the site too, so it's nice to help out those who help us.