I have been reading on the 4-bolt, and it seems to be very strong!
But to be honest, my car doesn't see, or will ever see hard launches. I'm more into track driving like the nünburgring track in germany, and the rear end/axels in a car that sees that kind of driving doesn't see a lot of stress/hard launches. At the moment I don't believe that my intentions justifies a 4-bolt rear end. Maybe I'm wrong??
Complete 4-bolts are in my opinion very cheap, but the shipping quote to Sweden will most likely be both my testicles