I've been trying to find the right MTB jersey for a long time now and couldn't find a viable option. Either it didn't fit well, I didn't like the material, or it didn't have the functionality. I really like this jersey. It's lightweight and fits great. I like having the two rear pockets (though I wouldn't put a phone or anything very heavy in it as it pulls the shirt down pretty easy) for GU or keys. I'm 5'11", 175 lbs and the medium fit great.