I would have to agree on the hopup theary, the first thing i did when i got my cam249 is m120 bearing spring guide, 9.6 3600mah batt. and a deepfire titanium teeth piston. If you look at how the little hopup peice (dont remember what its called) sits in the hopup you'd understand why it can cause enough back pressure to break pistons, you can run a 9.6 batt in one, just take apart the hopup and shave a small amount from the little hopup piece, and you're good to go.
as for star vs ca. in my opinion (having handled both weapons) i like the CA, first the star is plastic, and the weapon is so large that if you trip and fall you're liable to break something easier than with the CA. 2nd if the star's box mag mount happens to break you are shit outta luck since it will only take proprietary mags. somepeople think that being able to use Standard m16 mags is useless, i disagree however. ifyour box mag jams or stops working altogether you still have a way to fire your weapon.
I could go on. all in all both weapons are excellent, the ca is WAY more realistic, so if you have the muscles to handle it. My humble opionion is to go with CA
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