Another option you could consider would be AEPs, they are simple airsoft guns that are powered by tiny mechbox boxes and often come in the shapes of glocks, mac10s, MP7s, M93rs or skorpians. With a good quality brand like Tokyo Marui they are guaranteed to last if they are used appropriately and well maintained. However the only downfall is that they all shoot less than 280fps, and the upgrades required to bring them up to anywhere near 300 are extremely expensive.
This community has extreme varied opinions so at this time I would request that you narrow your parameters before continuing on or else you will simply just get a criss cross smattering of info of arguments about whats good from all over the board.
Since you are not dead set on gas electric or spring, I would recommend creating a list of which model of firearm you would like your new purchase to take after and how much you are willing to spend. Example : M9, and $150
Then you could explore the options of what is available in that model and in that price field.
"Its only a little bit on fire"