Pros: Sturdy, all most no maintenance needed. However will last longer will routine cleaning and oil. Tippmann provides there name brand upgrade kits (Expansion chamber, cyclone hopper, Response trigger kit) These all come with instructions and everything you need in the box to install. Vast majority of aftermarket parts and barrells. Most paintball fields & shops carry parts for the tipmann series.
Cons: Gun is heavy, all metal body along with internals creates extra weight. Gun is not the most accurate, consider upgrading barrell. Gun is Semi-Automatic out of the box. Do not expect to run onto the field like rambo. Consider E-trigger/Response trigger upgrade to turn to full automatic. Not easily accessable to mods, must always take entire case off gun while others now carry field stripping pins.
Tipmann 98 Custom ACT 
