Definitely a great tool!
I use GR since version 2 basically for practice but I've used it in a few jam sessions as well. If found it quite difficult to blend in with the other players' guitar amps, since I was the only one being stereo via our small PA and the others just playing their amps. Maybe micing the real amps would have been a good idea. I didn't have a good feeling about using it in a mix or session until version 4 came out. The control room tipped the scale for me.
I read in the audiofanzine article that to be unable to change the mic position in the control room is listed as a "con". To me it is a big pro because when you mix different mic signals from different amp cabinets (that's the purpose of the control room), the positioning of the mic is one of the most important things as to avoid phasing. Please note that I am no expert on micing and mixing amps though.
German sound&recording magazine did a preview in their 2009/10 issue (p. 32 ff) with an interesting interview with studio guitarist Peter Weihe, who owns this control room in real life. The GR control room is a simulation of Weihe's setup that has been carefully layed out and tuned for years and features some of the nicest cabs and mics. He uses two vintage Marshall 4x12 cabs (one early 70s, one late 60s which got "scanned" for GR4), a closed Fender 2x12, two old Vox cabs (one Blue Bulldog, one Celestion), an Engl Box for heavier stuff and whatnot. Mics were Sennheiser MD421, Shure SM57 or EV RE20, Royer R-121, Beyerdynamic M160 and a few condenser mics like Neumann U47, U67, U87 and U89. Mic preamps are API, Neve 1084, Massenburg GML and Siemens V72S (rare variant to be found in The Beatles' console). According to s&r the setup varied from cab to cab. German Gitarre & Bass magazine also did an review on GR4 in their 2010/2 issue (p. 189 ff) but it had just basic info on the Weihe angle.
The paragraph above is basically just a translated / summarized excerpt from the sound&recording article, but to get back to my previous statement that the missing mic positioning option should be a pro instead of a con: I have not alway been a fan of the "less is more" principle but in this regard I feel it is true. The control room delivers great sounding cab simulations modeled after a real, carefully aligned and proven setup. Every new mic position would have meant diverging from the original setup. The whole design of the control room is based on fixed positions and that's the reason (among others) that it sounds good. Of course there are other ways to obtain great sounds and other amp and effect simulation software proves that. It's just one way to achieve this - to my ears - great sounding simulation and I for sure wouldn't be able to buy all the stuff that is mentioned above and put it in a cab-room
Cheers
Tim
