You're in a whole other ball game if you're choosing between a mini and a Vibe. The Vibe is meant to be a very easy to use and consistant beginner marker meant to take the frustration out of using some of the "less-valued" guns out there.(Reliability, consistancy, accuracy, etc.) Basically, it's a very affordable EP that's pretty darn easy to use and maintain. Mini is more of a mid-end thing, so it's your choice.
if you want a good barrel CP barrels are really nice and accurate and you can get the 1 piece for 30 bucks on the website in a variety of sizes and color, when i bout mine i had 3 day shipping and it was about 40 bucks
I've always been partial to the j&j edge kit. Lots of options and up to 5 different backs. Five backs and three fronts for $100. I had one for my phantom and it was great. I ordered one with my vibe, but they haven't come in yet, so no experience with the edge on the vibe, but alot of people love em.