[ringring]

You mention the shop.

I wouldn't say the guns in there give you a great advantage. The default guns are pretty good all-rounders.

The exception are the 'other' guns for a max. ie if you want to dual-wield AI, which I'd recommend then you have to shop for it.

The other useful thing in the shop is the boosts.

Anything else from the shop you need a reason to buy. For example, do you want to be really effective at very close range (and therefore bad at long/medium) or you want a gun with more controllable recoil in order to be more effective at medium range?

Example: For me I prefer to be able to fight at a slightly longer range so I purchased gun with more controllable recoil, but they don't hit as hard at close range. However, on my medic class I like the T1 Cycler so I still play with that.

Last tip, at first for infantry put certs into forward grip, compensator, reflex sight (optional, if you like the standard stick with it) and nanoweave.