disagree with the idea, if your really hurting for ammo, your primary synth will last long enough to scavenge more, if you need special or heavy ammo, then your opting for it for the damage type / output, so you will get a limited use. no point having all of them, as you'll just replace all the other ones, and the cool down limit is there to stop you relying on it for unlimited ammo, the five minute timer at least makes you choose between burst damage or longevity.