To play or not to play hacked roms  

Well, don't know if these hacked roms even work... This is actually the risk you have to take, when you buy a hacked rom.
On the second hand, if you are starting to think if buying hacked roms is a good or a bad thing, then you should use your common sense. My opinion is that you should NOT buy hacked roms. Yes, they are cheap, but buying hacked rom actually leaves the original developer out of money and therefore they can't make games better.

Good luck

Hacked roms are just like gameshark for playstation. Those who buy it is either those that wan to unlock "secret character" fast or just don't feel like wasting lump sums on the original one.

Don't buy hacks download hacks for free. Never pay to buy a hack video game because you can always download it or get it for free on the internet.

No, even though most of the rare pokemon can be found easily in those games, it's still illegal to play them because they're hacked. A friend of mine back then became a victim of the said ROMs. He doesn't know anything about pokemon then, and a Pokemon Perla- I repeat, Pokemon Perla (not Pearl)- was offered to him for a price. Of course, he, not knowing what to do, bought it. Then, he showed it to me the time he bought it and I was surprised to know that there were many legendary pokemon in the said game, just at the start of the game. Heck, he found a Sneasel, and when he leveled it up, it evolved to a Zangoose! Those ROMs must be terminated and the buyers must not buy them, since they're illegal.

Actually hacked roms are not really for sale. You can download them on a certain site. In fact i even made a hack version of RUBY myself. ITs called pokemon 123 version where you can catch all the pokemon with this version.