Google Voice

Have any of you ported your number over to google voice? How is the experience? Seems like the only major bummer is no MMS. Is there any kind of work around for that? I'm thinking of picking up a nexus 4 and moving over to tmobile, and figure it might be a good time to use google voice if it has any big advantages. I kind of remember reading that when you call someone it will not come up as your number, but as the carrier number associated with your google voice number. What are your likes and dislikes? What should I be aware of before doing it?