I've dealt with both since the 98 was released. The 98 USED to be the betterr gun, but the new ones are....well point blank there not worth a crap. We've had 14 brand new in box guns come in as rentals in the last four months, six have gone down within a month of opening them. I guarantee you I do more maintenance than the average noob does to there gun on them every time as well. I've fixed four different brand new customers guns in the last month(only ones I can recall right off the top of my head, I fix a lot of guns . I know the numbers on our rental fleet for inventory and purchasing purposes...) as well. It is very much a new generation phenomena.
Our spyders can be a bit finicky, but we haven't had 2-3 breakdown(and understand non of these are within a year of being as new as these tippmans)) in that time frame. The sad part is, we're fixing the new guns by pulling valves out of worn out 5+ year old ones.....that's how bad QC has gotten.
Kingman has come a long way in the design and quality of there guns, while tippman has let there QC fly out the window. I'd take the VS1 over the tippman any day at this point. The gun is no more poorly built, and the spyder is a helluva lot easier to fix. I hate the tippman clamshell design. It was fine when the didn't NEED to ever be pulled apart, but not now...spyders strip down with four screws in sub 10 minutes.