Oddly enough, because the Castlevania Dungeon is in need of some stage screenshots from the DS games, I'm finding myself playing Order of Ecclesia on my PC.
No$GBA is the emulator of choice, it seems.
It runs on my PC at nearly-proper speed and only experiences slowdown in the teleport rooms of OoE (which if you guys recall have a big 'water bubble' effect going on in the chalice of teleportation).
DS emulation is possible on my system, and I believe yours and mine are on par with one another (yours might be superior, actually).