Firstly, the Blitz is built on the koas model, plus an adjustable blade trigger, ramping (near fully automatic) board, eyes, regulator, macroline system and is the "middle grade" in the Azodin line. The kaos and GTI are entry level markers, and the Blitz was designed as a mid level gun, so there is really no fair comparison. In addition Piranha gti is a relatively old, and in general low quality gun compared to the entire Azodin line.
Azodin is, in general, able to make better quality and longer lasting markers than their Spyder counter-parts, because of their improved design. This particular model, the Blitz will perform the same, or probably better than the VS2 with slightly less cost.
yeah
15.
If the back is auto-cocker threaded, then yes.
If the back is auto-cocker threaded, then yes.
you cant "burn out" a paintball marker
yes. but for ten more dollars you can get an Azodin Blitz, which comes with a nicer regulator, trigger, lighter striker, better detentes an a better customer service
Yes. Since it has an adjustable feedneck it can take any loader.
If the upgrade is the black heart board, get the vibe. If the upgrade is anything else get the blitz.
Since the blitz has eyes, it can shoot fairly well with cheap 30 dollar hoppers. If you want something that will keep up with almost every gun, buy the Invert Halo Too for $60
It all depends on what you can afford. For the $100-$200 range, I recommend the Azodin Blitz. The Blitz will work great stock with no upgrades and that allows you to save money skipping upgrades to purchase a new gun later on. The only upgrade you should get if you do is a new barrel because they use autococker threads and you can most likely share the barrel with your new gun. The board can also be flashed with the new updates or add new modes by sending it in to Azodin or going to a pro-shop that is a certified dealer for Azodin products.
best is a matter of opinion but by a large margin the spyder fenix or azodin blitz are currently the lowest priced markes ($150) that have the most features on them