I've been switching back and forth, and so far I think Felger and Mazzarotti blows away the Big Show. Just much more substantive sports talk.
I haven't listened to, and don't plan to listen to Tanguay and Zolak, since I can't stand either of them...plus, Dale and Holly is by far the best thing on WEEI.
And the morning show is lame on both channels. I got sick of Dennis and Callahan a long time ago, since they rarely actually talk about sports, and when they do, it is incredibly over the top, reactionary stuff that drives me nuts. So I have listened to the new Sports Hub morning show, and was even less impressed. Its basically a couple mediocre Rock DJ's acting like they care about sports. I've basically given up on the sports talk in the morning, and listen to the Sand Box on WFNX instead.
Ultimately though, what this comes down to is there is now competition, and another station to turn to during commercials. I don't think either station will blow the other away in the long run, and hopefully they will feed off each other, and keep getting better.
Oh yeah, and by far, the best part of this whole thing is WEEI changed its commercial format in order to keep listeners around, now that they have competition. They have stopped running 15 minute commercial breaks a couple times an hour to 1-2 minute breaks every 10 minutes or so. It has made it SOOOO much better to listen to, and was a genius move, since they would have really lost a ton of listeners if they hadn't done it now that they have competition.