Hoenn's still reigns supreme to me. Although I really liked Sinnoh here, sound way much better than the original.
Kanto's. Don't forget the Unova Gym Leader theme was also remixed.
Sinnoh. Least busy, and the best use of the parp trumpets yet. Kanto would have gotten a vote, but the beginning sound bites were used too little.
Kanto for me, as it was the only one that gave me goosebumps. :p
Hoenn is definitely the best imo.
Kanto > Johto > Hoenn > Sinnoh
Sends a shiver down my spine. Reminds me of this time where I fought Misty's Starmie in Blue and it used that scary as fuck Bubblebeam attack. Probably the best remix of Kanto Gym Leader theme I've heard yet.
Better than HGSS theme IMO, which kinda lost the soul of the original Johto gym leader theme.
I adore the eerie beginning, but then it gets kinda meh. Although listening to this theme a few times made me appreciate how calm and subdued it is compared to others.
I like it, but the other themes are just better, so it takes the last spot. Sorry Sinnoh...
Hoenn. HANDS DOWN! It's better then the other ones.
What? no love for Johto? :( While all of these put a smile on my face, I'm particularly fond of the Johto remix.
I don't have much of a vote right now, but I might do it after I'm done typing this:
Battle! Gym Leader (Kanto) - I'm not sure entirely if the beginning is meant to invoke something like Pokémon Stadium, but I do know that at the very least the general theme around it is using those electronic synths to produce a sort-of Game Boy feel.
Battle! Gym Leader (Johto) - Same case as Kanto, but seems to be trying to invoke a sort-of Generation IV feel to it as well (given that, besides similar sounds for IV and V, was also the last game released in the previous generation, meaning people are most likely to be familiar with it as of right now).
Battle! Gym Leader (Hoenn) - The beginning really invokes a Generation III feel. Truth be told, I never really liked the sound of Generation III's music (perhaps one of the reasons I never played Hoenn or Kanto/Sevii), so this music is good news for my ears.
Battle! Gym Leader (Sinnoh) - I'll agree with @Mitchman and say the parp trumpets are excellent in this. However, who gave Junichi Masuda the instruments Jun Senoue used in Sonic the Hedgehog 4: Episode I? Those synths...just...I don't really like them that much. The rest of the song is excellent, though.
...ok, still not decided (perhaps because I desperately want to say Unova's Gym Leader theme). Perhaps this thread could have at least had the Pokémon World Tournament tag placed on it...no, wait, that doesn't help at all. The first Gym Leaders you fight are from Unova. *facepalm*
I'm now curious as to whether there is going to be a Champion edition of this poll, because I have a definite vote for that.
I'm stuck between Kanto and Sinnoh. Both were pretty awesome.
kanto- very cool remix but no steady beat
johto- beginning was off but rest was good
hoenn- always had trumpets, but not anymore:(
sinnoh- added a lot more sound to original