I have both, and both are very easy to maintain and clean.  However, you have to be a bit more gentle with the Ion, due to the fact you have electronics and macro and micro line hoses to worry about loosening up.  Then again, it's pretty easy to loose the sight sping on the 98CPro.  I can strip clean both markers in about 15 minutes, each, but I rarely take the firing house apart on the Ion (that would add another 10 minutes or more). 

Just a hint, for the Ion, get a ball headed allen driver.  That'll make it alot easier to remove the grip frame screw from under the trigger guard and behind the trigger frame.  Otherwise, if you use a regular allen wrench, you'll only be turning the screw about 1/4 turn at a time.

oletimer wrote: Ion's are crap if you mess with them they break there also not as durable as a tippmann.

I have both.  Yes, the Tippmann is more robust, but the Ion is extremely easy to work on, also.  With the Ion, there aren't parts to loose, like the sight spring on the Tippmann.  I'm guessing you either don't have an Ion or are not very saavy at taking things apart.  I installed a friends QEV, Kila detents and new feedneck in about 20 minutes, start to finish.  The only thing you have to be gentle with, is taking the trigger frame from the firing chamber (you have to be a bit gentle pushing the board up and out with your thumb) and then be gentle not to throw around the board-hose assembly.  Other than that, piece of cake.