It absolutely works. Also, technically, you'll be using compressed air, not nitrogen. You can get nitrogen fills rarely, but compressed air (called HPA for High Pressure Air) is easier, cheaper, more readily available and, since air is mostly nitrogen anyway, does the same thing.
You'll notice more consistency between hot and cold weather as HPA isn't affected by ambient temperature nearly as much as CO2 is. HPA is far preferable in fall, winter and spring because CO2 just doesn't expand as well in cold weather. Summer doesn't matter.
Another nifty thing about HPA is you never get liquid in your gun like you can (and often do) with CO2. That saves wear and tear on o-rings and other internals.
All Tippmann guns are HPA ready right out of the box. 98's, 98 Customs, A-5's and X-7's all are ready to go with HPA when you buy them.
What's the catch? The HPA tank's cost. Whereas you can get a CO2 cylinder for around $25 (give or take a 5-spot) an HPA tank like mine (4500psi - 68ci) will cost you between $175 and $250 depending on vendor, and whether it was bought in a store or on-line. My tank is carbon fiber, the lightest kind. You can get a steel tank for a LOT less, but it's heavy. Real heavy. Aluminum tanks are the "tweener". Lighter than steel, heavier than carbon fiber. More expensive than steel, less costly than carbon fiber.
These tanks all come with a regulator on them. All you need to do is screw the tank onto your ASA connector on your gun, or hook it up to your remote line, whichever you have.
I played one scenario with CO2. I've been using HPA for the next 9. It's money well spent if you are serious about playing paintball. If, however, you are just playing around and occasionally running rec-ball (which is what many, many people do), then stick to CO2. At that level of play it's not worth the cash outlay.
There's my two cents. I hope I've been helpful.
Woodman out
Proud member of Team Black List
"The society that separates its Warriors from its Scholars will have its decisions made by cowards and its battles fought by fools."
Thucydides