Couple nights ago I listened to the Blomstedt/Leipzig B7, a live performance from '06, and I can't offer enough superlatives. Just first class in every way--orchestral execution, SQ, and conducting that lets the music speak for itself. I found myself thinking that it's not just as good as it gets, but as good as it can be, quite a rare sentiment.
I've always loved Blomstedt's Dresden B7, having had the vinyl issue for many years, then finally scoring the CD last year. I need to listen to it again. Jochum/Dresden is another excellent performance though he includes the now generally discredited cymbals and triangle in the slow movement. I can't remember if Blomstedt used them in Dresden, but he didn't in Leipzig.
I must confess that I have a bee in my bonnet about B4. For me, the horn triplets in the scherzo must be both crisp and prominent, but in many an otherwise excellent recording, they're buried. My first recording was Walter/Columbia SO, which still stands up pretty well (especially for 1960 and a pickup orchestra), and whose horns embarrass a host of other performances. The two more modern recordings I'm aware of with decent horns are Bohm/VPO and Blomstedt/SF. Haitink/RCO (not VPO) is respectable, and Klemperer is not bad. I listened to Blomstedt/Leipzig last night, and while overall it's as good as their B7, the horns in SF are a bit better.
While this is probably a minority view, I also like the original B4 (without the "hunting" scherzo). That version's scherzo has a start-stop quality that I found off-putting at first, though I grew to like its stormy character (no current political reference intended). To me the finale seems more organic and builds to a powerful finish, as opposed to the "mainstream" version where I've always found that the ending is a little hokey and seems tacked on.