How about an additional point to make?
What kind of guitar sounds are you recording/into? Are you into dark heavy sounds? Do like bright, biting tones? Clean, or distorted? These questions will play into your decision as well. The Great River has been described as heavy with a lot of "iron" in the path. Some people call it a "dark" preamp (although I think that's a misleading term as you can get some very bright open sounds, especially if you play with the impedence and loading swithces and depending on your mic and micing technique). The Pacifica is known for being open with a special "something" in the high end. Here is a post with the Pacifica on vocals and acoustic guitars:
http://www.gearslutz.com/board/showp...2&postcount=27
The Pacifica sounds amazing to me on the vocals and is the clear winner for my tastes in this test. I actually preferred the Millenia for the acoutic guitar, however.
As I said, the Great River pre has a lot of versatility in the sense that there are plenty of switches to play with along with the gain and ouput. While the Pacifica doesn't have the tweakability (although many users report a noticible difference in sound using the pad) that the Great River has, many of it's users (if not all) feel it is very, very versatile in the sense that it just seems to "work" on everything the throw at it. In fact, maybe we can get Brad to mic up a XXX for us and post some sound clips comparing his ME-1NV to the Pacifica. What say you Brad?
What am I getting at? Well, I think you and I need to get both preamps! For me it was a question of which do I get first. I chose the Great River for my first purchase because I'm into, and record big, heavy distorted guitar sounds and I believed that the Great River was going to get me there. I didn't come to that conclusion by myself. I read tons, and asked lots of questions and got advice from people who's opinions I trust impeccably. I did not audition the Great River before I bought it, but I have never, even for a moment, regretted purchasing it. I have been getting the best heavy, distorted guitar tone of my entire career with the ME-1NV (actually I have a pair now). If I wasn't so convinced that the Great River should be first, I would have done the obvious thing (which is what I suggest you do if you are not so sure after all of this) and gotten both into my project studio and auditioned them. I am now ready for my Pacifica. It's a different design and as you have heard a different animal althogether from the Great River and I am excited to have it in my studio. In fact, I will be auditioning the Pacifica in Peter's booth at the AES conference this Saturday. I can hardly wait. Anyway, sorry to ramble. Hopefully you can tease out something useful from this.
Best Regards,
Mike.