all aegs are essentially have the same working functions such as all have a set of planetary gears that move a piston in a cylinder powered by a motor to create air propulsion to fire the bbs. Quality wise is the same as paintball you can go cheap with your regular AEG (TM, KA, G&P, VFC etc.) or go for the ultimate set up such as PTW/PTW5
it all depend how deep your pocket is. As far as MP5 I use a PTW5 which by far is the best MP5 out there but the cost is prohibitive for new players (around $3K after all the extra mags, batteries, cylinders) or you could settle for a Classic Army with a bit of mods much like a tiippman A5 with mods. ultimately it is all up to you how much you want to spend. remember buy cheap buy twice and the term you get what you pay for has never been so real when it comes to airsoft.
Last edited by wildcard; April 11th, 2012 at 20:02..