I used my Invert Mini for the first time on Sunday, such a boss marker, the firing rate is ridiculous, so accurate, so damn light, reliable, and easy to work on if need be, a very simple thing.
2nd hand can easily be had for £150, I paid £180 but was the limited edition and pretty immaculate.
TM7 would be a better choice, goes full auto and works really well ( oh no I mentioned full auto but I won't start that argument for a few months when I decide to attack UK paintball over claiming Paintball guns are firearms ( which they are not ) after one discussion with a retired fire arms officer ) but look into that it's awesome, or a X7 Phenom, I used to use rock that until it pissed air.