I just wanted to clarify though. Your EOS Freak Jr. will work in the NXT but not the SFT. NXT is impulse/ion/nxt/luxe threaded and SFT has it's own thread set (usually "SFT threads" or "Shocker threads").
Parker and Humphrey noids are very similar, and are interchangeable; however, on parker noids, the upper board is soldered to the solenoid body while the Humphrey upper boards plug in. From a maintenance standpoint, the Humphrey noids would be better because if you get board damage, you can unplug them and get a new board for 25 dollars.
Reflective eyes from an SFT will work in an NXT (you have to switch your board setting to reflective eyes) but not vice versa. the SFT is only milled for 1 ribbon so the break beam will not fit in the body.
NXT and SFT frames are interchangeable as well. Triggers are specific to either frame. Feednecks also have different threads.
I'm pretty sure most of the BOLTS will work in both guns, but some of the cans are not interchangeable. The stock and HE firing cans are closed, solid cans. The SFT has two vision holes in the side of the body. If you put a ULP firing can in the SFT, all of the air will just flow out of the holes. NXT is compatible with all bolt assemblies and firing cans.
If we're comparing completely bone stock guns, the NXT will outperform the SFT because it comes stock with an HE bolt. The NXT has more new parts still available for it even though the gun has been discontinued for 4 years now but there are TONS of parts available used for both. However, most of the SFT's in the classified section will usually have some pretty good upgrades and are definitely cheaper. When it comes down to it, it's mostly preference. I've only shot SFT's. I like them a lot because I'm weird like that. It's the same reason why I like driving my mk3 jetta. It may be a little beat up but I can make it my own for cheap and it has soul.
I hope this helps!
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