dont get a gas rifle as your first gun. Each gas system is different so finding spare parts will be very tough. mags are also 50 bucks each as opposed to 10 for AEG's.
Failure rates are similar between the two types but if something goes wrong with a V2 or V3 mechbox anyone can teach you how to fix it, and where you can buy parts.
TM MP5k PDW -ris, stubby grip, DNTC, electro
KWA USP 45
"SNIPER" is NOT a gun. It is a person. Saying "I use a sniper" is like saying "I fly a pilot".