I have used a spyder pilot acs and a spyder victor
I have not upgraded my VS3 at all. I left all of the stock parts on it.
you probably want a drop foward and a barrel
The rocking trigger is awesome
good eye anti chop system
great low pressure system
The feed neck sucks
My regulator leaks
Needs drop foward
The best thing about this gun is that it is fast. The rocking trigger 2.0 is awesome and if you have fast trigger fingers, you can easily empty your hopper in like 12 seconds. the anti-chop eyes have not failed me yet. It has infact saved me from a few ball chops. The regulator and low-pressure system are awesome. the ad braggs that it will run at 200psi, but i realised that that won' t shoot the ball too hard so I run it up at around 300psi which is perfect. The regulator was leaking the first time I used it but I took it apart and it was only a broken o-ring. (easy fix). If you get this gun, you might want to upgrade your barrel, and get a drop foward, but I havn't done anything yet.
I think that this gun Is a good gun for the price. it's not the best but it has few weaknesses. You won't be dissapointed.