I've done some long trips (~200 miles, ~60 miles) on track drops, bullhorns and risers, and it's all about preference. Track drops weren't that uncomfortable, being in the drops for climbing wasn't as bad as I thought it would be. Bullhorns offered the most hand positions, but most of the time on these rides I was simply placing my hands close to the stem and mashing. I'm sure if I had road drops breathing in the drops would be easier, track drops seem to close the diaphragm.