It is a low quality, cheap starter marker. It shoots, and that's about it.
The spyder victor is a more reliable gun than the JT. You should also look into the Azodin Kaos.
Tippmann 98, very durable and easy to fix.
No, The Electra is Spyders "step up" from the victor. It is inside the same as the victor, but also has electronics and other features. The same with Tippmann, Azodin, and many other companies, they release a low, mid and "high" end gun together. The victor in this case is their cheapest and most "bare boned", then the Sonix, and then the Electra.
Air regulators, barrels, hoppers, asa, and trigger wells.
They are the same gun with slight variations. The sonix has a hand grip, clamping feedneck and different ASA hose and the victor is slightly cheaper because it doesn't have those things. Neither of these guns are very reliable or what could be considered "good" I would look into the Azodin Kaos before buying either one of these.
no pirahnas are lower quality knock offs than spyder, they are not too bad for starters but spyder is better if you have a choice
Tippmann 98's, spyder mr1/victor, and azodin ats/kaos are good to start.
Kingman Spyder.
The salvo has more accessories and has a better feed neck and stock then the Mr1.
It depends on what you are going to use it for... If you are going to play more speedball, get the sonix... If you are going to play more woodsball, get the MR1.
The G3 is a better gun not just from a personal stand point, but obvious reasons. The G3 is the lightest marker ever produced. There are many more modes then the spyder and the metal is of a higher quality. The Spyder is also an older gun then the G3.
Disassemble the gun, and replace the back cap with the stock or take it to a paintball store, and ask them to.