[nhlducks35]

Right now I'm still torn between which of these headphones to get. I would be using them for the bus and school, and would be using just my iphone to drive them.

I can get a pair of 1Rs for about $160 and a pair of Momentums for $210.

 

[thievesarmy]

I think these 2 have been compared to each other quite a bit, as they're basically positioned the same. I can't speak on the Momentums, altho I have the MDR-1R and like them a lot, BUT i recently got the AKG K545 and think they are far superior. The Sony's are more comfortable, I think a lot of people like the sound of the Momentums but the ear cups run small, so the fit has been an issue. The AKG's are a bit more in price, but I think they're worth it. the sound is killer.

 

[raidenwolff]

If the K545 are similar to the K550, then I would urge you to try them all first before buying them. As much as I love my K550, I don't think I would be happy with them if I listened on the go. 
 
On the go, I'd opt for a more 'fun' sound than the whole analytical, flat, 'reference' signature. Because when I'm on the go I wouldn't be completely idle - maybe I'd enjoy the scenery on the bus ride, or read a book, or play with my iPhone. I wouldn't be completely focused on my music anyway - not in the same way I do when I sit down at home and listen to classical music, for example. 
 
If you are like me, then go for the momentums I would say.