I agree with malkin--some jerseys from some brands work; others don't.

I'm 6' and should be a large, but always by XL for length.

Some of Voler's work well. I have some that are perfect and I wear a lot; others like TE's Flourishes jersey is long enough, but puts me into contorsions to use the pocket ( http://www.teamestrogen.com/prodTE_602.html ).

This one -- http://www.teamestrogen.com/prodTE_603.html -- works well. I've worn it enough that the white is lacking in whiteness now. Nice summer jersey.

Also, the Smart Wool Ewetopia long-sleeve jersey (sold out, but I'm hoping there will be another in fall) is wonderfully long--both torso and arms. I wear it constantly in cool weather. The short sleeve version is also long enough, but I didn't like the summer weight fabric.