I've never used an X7 or a 98 but...
A friend of mine uses an X7 and has had nothing but trouble with the feed on it. (I think it's called a cyclone feed?) When his CO2 bottle gets below 1/4 it does not feed reliably, CO2 remote or on the marker. I don't know if this problem would persist with HPA or not.
His response trigger requires almost constant adjustment depending on how full the CO2 tank is.
He also likes to carry wrenches around in the thing and it rattles more than the muffler on a 1978 Dodge Omni.
It's also
really bulky, and you're considerably smaller than him so it's going to be even worse for you.
He's made several complaints about the flatline he bought for it, it requires expensive paint otherwise he gets lots of barrel breaks.
And he's always screwing around with some bolt you have to remove to remove the barrel? I don't know what he's doing wrong, and I can't imagine why Tippmann didn't just give it a threaded barrel like everyone else does. Maybe threaded barrels work too well...

I have video of him somewhere wrestling with this barrel in the middle of a match, I think he got a squeegee JAMMED in the flatline and couldn't get that bolt out. Meanwhile there's a firefight going on around him.
Of course, he's can be a bit of a dumb@ss at times and probably didn't RTFM. Try it though, maybe you'll like it.
Make sure you talk to Dave about the X7 and the 98 before you make a purchase.

He has experience with both.