Eh. All things considered I got sick of Garguilio and Corino at times. There's such a thing as having too much fun on commentary. D'Lo and Coach did, and to a lesser extent Corino and Garguilio did as well. Otherwise, they were pretty good.
JR and Lawler seem to be decent announcers when paired with anyone other than each other. For evidence of that, look a the JR/Heyman and Lawler/Coach tandems. INFINITELY better than JR/Lawler. They need to throw Coach on Raw either replacing Lawler or as a third commentator because GOD, do Ross and King suck now.
Cole and Tazz have evolved into a very listenable commentary team. Tazz is very good and Cole is quickly improving from the peice of crap announcer he used to be.
Mike Tenay and Don West, in my opinion, are currently one of the best teams out there. Tenay's a great PBP man and has earned his nickname "The Professor", and West's excitement is great. His knowledge of wrestling and moves and all that isn't so great, but here's a guy who loves what he sees and wants everybody to love it as much as he does. And he's definitely not the same Don West who just went "Wow, look at that move, guys!" He's actually made some astute comments on what's going on (Most notably saying that AJ Styles probably tapped out quickly in the second match of their best two out of three series to save his strength for the last one).
I can't judge Coachman because he's turned heel and stuff and I haven't gotten a good sample of his heel work yet.