If you want a new gun for realism I always run GBB pistols, they are the most satisfying of all airsoft guns imo.
I would only ever use/advise TM, all others are sub par in every aspect other than ‘got heavy metal slide’.
The TM FNX is an absolute beast out of the box - hopping silly heavy ammo out to 55-60M accurately - bog standard!
TM HK45 / USP / Glock G4 are all 50M guns.
Back to rifles…
They all cost the same to buy/build really when at a high level, however running costs don’t.
IMO worst to best;
HPA offers nothing but ROF and ball ache when utilised at full auto FPS’s.
Its best used for DMR and Sniper.
GBBR is fun, yes the MWS is very simple/cheap to upgrade.
It is best suited to those who take considered shots.
Good for milsims & CQB where you can bomb up more often.
But as said above makes for a very heavy load out and gas can be a pain to keep on top of.
If you want a cheaper GBBR fix the TM MP7 is the way to go, it’s loud, violent, 50M capable and down right fun!
Leads us to the inevitable, TM NGRS.
Ive built a lot of guns, if you want the most performance in all aspects.
Even if you ran a pretty stock NGRS you’ll be impressed, just change the nub and fit a nice 6.03 barrel.
If you do any more than that you need to go the whole hog inside really.
I don’t know if you have pistols, but if you don’t and you want the best performing setup in 99% of scenarios with the most enjoyment run a TM pistol and NGRS 😉
Do let us know what you decide 😁