You probably wont get a lot of "valuable" information on one vs the other right now from members other than the ones with LS3 conversion say:
I have better/wider cam selection
I have good lifters now which shops say is a weak point
I spend more money lol
I think I have an ls3 now?
Those with VVT:
I have the best of both worlds
Its cheaper and easier to install
I kept my weak lifters or I chose a VVT cam with afm delete and got rid of them for a little more money.
I gained more low end torque then you LS3 guys and maintained Same hp as your cam.
If you want a big comparision what you see from the vendors is the best for now as really VVT cams for the camaro are just now starting to get into peoples mind and engines. If you want more one vs the other from actual drivers then wait.
That will give you some time to do the other things!!! Not only do you have to decide ls3 vs VVT but also VVT vs VVT with afm delete