The set-screws should lock them in pretty well.. But you could try using the temporary Loctite.

Actually the question toward suspension choice was directed toward liborlad. What suspension are you running?

Actually I use Titanium Center Driveshafts and 8mm Hardened Steel CVDs and they been holding up fine.
I am a basher too, and I hope to do some crazy jumps later on and see how these parts hold..LOL

I rammed into stuff, flipped and cartwheels at 40+ Mph and it still holds but like some has already said, anything and everything has a breaking point.

@libordad; What brand titanium cvd's did you bend? UE's? And was it a twist or a real bend?

And about the lighter the truck theory;

They manage to reach 50mph on a 12 cell e-maxx! Now that's crazy fast on such a low cellcount if you ask me..

I'm running with UE widetrac, which I'm very happy with.

I bought some GPM Ti driveshafts on Ebay, I don't think it was the best purchase I ever made. I've got slight bends on 2 of them and the wear on the drive cups has been pretty rapid. I've just installed some RDlogics steel shafts and they seem to be fine. If they don't last the pace I'll be switching to UE.

Was it the cvd type, or the other one?

It is a type of CVD however, it was not the usual design followed by, MIP,RDLogics,UE etc.

I got me a set of these, just wanted to know what they are up to.. That is the cvd type i meant

It looks a bit different from the one you showed, the actual cvd bit of the shaft looked more like this:
http://www.rcxshop.com/product_info.php?products_id=707