Anyone ever play Battlefield: Bad Company 2?

I recently got my hands on the "Ultimate Edition" which includes 1943 and a bunch of DLC for online (which I probably won't get any use out of because online shooters aren't for me). I've never played any of of this series but, through the first couple of missions, it seems pretty good.

Anyone have any experience? Is Battlefield: Vietnam worth a look (14.99 DLC) after I finish 2?