What is the best automatic airsoft gun?

Best is a opinion, but I prefer the UTG M32 Master Sniper Rifle, It Has 430 FPS and Costs $80 Without Scope. I bought mine From PyramidAir.com With Scope, Bipod, Sling, and Extra Mag for $120. The best Airsoft sniper by power is the Green Gas M700P Sniper Rifle Competition Modle, 720 FPS For $200 From Hobbytron.com But no one will play with you if you are using it.

700fps or more is illegal without license its considered a type two weapon and you can get in serious trouble--not recommended.

There is really no best airsoft sniper rifle, because there is a lot up to personal preference. All ARES sniper rifles are very good, my personal favorite being the MSR-004 because of its unique bullpup design. If you are looking for a semi automatic sniper rifle, the Reals SWord SVD is one of the best ones out there. There is also a large range of very good M14 sniper rifles and tons of bolt action ones in all price ranges.