I got HeartGold because it looked cool and I like the color gold. It was the second game I ever got, the first one being Platinum. When I lost my beloved copy of Platinum, HeartGold became my favorite game even though I got a new copy of Platinum. Back then, I didn't know there were version-exclusive Pokemon, so I figured I could just pick whichever one looked cooler. Even now, I don't think I would have chosen the other game, because I managed to get all the Pokemon exclusive to SoulSilver by global trading my dratinis I bred :) . Plus, with hoenn sound I now have linoones! And the Lugia I got in HeartGold is one of my most powerful Pokemon and is on a team with my Ho-oh. So, in the end they're so similar that it really doesn't matter which one you pick cause it can work out whatever way you want. :)