I use a nova700. Everything is tuned to perfection, polished, and it's got a trigger job too.
Recommended Upgrades:
A good D/F, upgrading from stock reg to max-flow, trying to get a SBS from sec8, and a 45 grip.
Strengths:
Works on volume, not valve dwell. It's extremely hard to explain in less than 5,000 words, but the gun works extremely differently from other markers. The flow remains relatively laminar due to low pressure, and is probably THE quietest operating marker on the market, period. The spool valve is exceedingly quiet, however, the barrel is what is the downfall of this gun, which is why I recommend a SBS (stationary barrel system).
There are tweaks and tunes to be done to this gun to make it better, but overall it's really good stock. They can be had now for a song and shoot as accurately as any gun out there, and my previous nova700 shot MORE accurately than my phantom, which is "the accuracy god" to most people. The gun is extremely accurate, extremely quiet, and has a really nice trigger pull when properly tuned.
Weaknesses:
It's top heavy by design. You need to counteract this with a good d/f.
The eurogrip sucks. Replace it with a .45 frame immediately.
They never work. To be honest, the only reason why people sell their novas is because they're to stupid/lazy to get them working right. So they pass it on to others, and novas get a rep for not working merely because people are stupid. Airstar went out of business, which doesn't help, but luckily one can find support in the PGI section of pbnation.com, or you can email me and I can probably help you out.
*THE BARREL*
The fact that the gun uses an ABS (articulated barrel system) is the single biggest downfall of the gun. The gun will fly around in your hands because the barrel is jolting back and forth with each shot, creating recoil, and "negative" recoil, where the gun goes foward. REALLY annoying, but with practice, you can achieve good accuracy. The gun itself is exceedingly accurate, I really mean that. But the fact that it jumps around ruins the shooter's accuracy, so it is thus worsened by the cause. Sigh. Anyways, it's great for things like single shots, taking about 3 shots/sec, and it can also rip when properly tuned too. I can hit about 14bps with my nova. It totally flies when you want it to.
However, the stock reg shoots down when you're going over 8bps for longer periods of time, which is why the max-flow is a good idea.
Conclusion:
The nova is an excellent gun. If you're a player who wants something for "snipuhing" and taking mainly pot shots from concealed positions, but also wants to have ripass potential, the novas for you. If only I could get my paws on a SBS....
The nova would rock if the fuggin barrel didn't jolt around...
If you've got the money, I suggest you take a look at section 8's new lunacy coming out. The nova is a primitive gun. It uses ideas way ahead of its time, but you can see that section 8 markers like the lunacu and darkstar are fixing all of the novas problems. I hang on to my nova because I can't afford a lunacy and I like the gun. To be honest, the lunacy is a better gun and has better design. I like to keep novas alive because they are the grandaddy of all spool valvers. The matrix, darkstar, mayhem, super nova, lunacy... it's all from the nova700.
Its a GREAT gun, but not recommended for people who are really serious for performance. I'd recommend it as a tinker/backup gun which is really nice. I'm a pump player and I don't shoot fast anyways, so a gun like the nova which has mad accuracy, great trajectory, super quiet, and also is able to blaze paint, is a good gun for me because I usually take slower, more aimed rof. It's almost a semiautomatic trainer. If you fire too fast, you'll lose your accuracy through the recoil of the gun. Anyways, I highly suggest it if you want to have a nice practicing gun or backup. Great gun, definetly is worthy of the full 10.