also consider the cost of the mods for both guns. If you don't like spending lots of cash on mods, go with the Spyder since the variable rate of fire is already built-in with the spyders. The Tippmanns can range from $80-150 for the e-triggers or response trigger. You can go with those marker bundles, but like the spyder fanboys, they'll tell you that you can almost get 2 spyders for the price of 1 Tippmann with the e-trigger. But then again the Tippmanns have a ton more cosmetic mods than the spyders!
Take a look at these buttstock upgrades for the A5:
Tippmann A5 and 98 Butt Stock
Spyders:
Spyder/Automag/F-4