Re: Which Barrel(s)?
Of the three choices, I'd choose the kit. However, I haven't heard a lot of good about the Evil kit, but I haven't heard much bad either. It does give you the option of sizing the paint to the barrel, which will seriously help with your efficiency and somewhat help with your accuracy.
However, if I were to choose from kits, that would probably be one of the last that I'd choose. I'd look into the Redz barrel kit, the Sceptor kit, the titanium bow (dang, can't remember the name of the top of my head!), a McDev Matchstick, a Freak or the J&J Edge kit. I'm not sure if the middle ones have Spyder threading available, but if they did, those are what I'd look for.
The proto one piece is a good barrel - I have it on my Rail and a friend of mine used his on an Autococker. Pretty much ball on ball, it looks ok but not that great, and you are limited to matching paint with this. I've heard it's pretty much like an Ultralight barrel, but I've never used the UL (don't want to spend 100 bucks on a barrel!) so I can't compare.
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