Well, I got the IPS-1 all set up last night. It was heavy, but not unbearable. Here are my first impressions:
COSMETICS
The IPS is a nice looking unit. Compared to the RPA-1, there are pluses and minuses for me. Seeing the two next to each other, I like the cleaner look of the IPS-1 face without the raised aluminum panels. However, the piano gloss black wood sides of the RPA-1 are really quite nice (although I can't see them in my center), and the illuminated meters on the front of the RPA are (albiet practically useless) much nicer looking than the LEDs on the IPS.
On a related note, if I were to choose between the MPS-1 and MPS-2, I would pick the MPS-2 because the only advantage of the -1 to me is the wood sides, and I can't see those inside of my cabinet.
PERFORMANCE
I'm with GR here on his first impression. There is an improvement, but I have to decide if it's enough to keep the unit. Please note that I am powering my mains with the RPA-1 and the center/rears with the IPS-1.
When listening to the "Fleetwood Mac - The Dance" DVD, the vocals were more clear with less background noise compared to when the center was powered by my receiver. It just all sounded more real. As with my RPA-1, this became evident when I turned the volume up louder than my everyday listening levels (which is what I do with that DVD anyway). With the volume turned up, I noticed that there was much less (if any) ear strain. That was nice. One of the songs on that DVD is what actually got me thinking that I needed an amp for my center, so I know it well and that was my best selection for trying out the IPS-1. I also tried out a concert from The Cranberries, as well as several scenes from Mr. and Mrs. Smith. They sounded great, but I'm not in as good of a position to compare the IPS to my receiver on that material.
ISSUES
Yes, there are some things that I don't like and/or concern me.
1. While in standby mode, the unit seems to be drawing more power than it should. This concerns me because this is exactly the same thing that I experienced with my first RPA-1. For the RPA-1, I contacted Emotiva and Lonnie said that it shouldn't be drawing more than about 1 W in standby mode. I was literally e-mailing him back when after about 24 hours of power being applied to my first RPA-1, it (while in standby) sent a power surge through my speakers and went into overload. Emotiva replaced that unit, and my second RPA-1 has been rock-solid with virtually no power draw in standby mode for about three months. I just wonder if this IPS-1 has a similar issue as my first RPA-1, and I'm concerned about it overloading. Once bitten, twice shy and all.
2. While in standby mode, this IPS-1 makes a noticeable (and I think loud) humming noise that I can hear from across the room. That might be related to the issue above. That alone for me is a deal breaker. I can't stand humming sounds, and I don't want one to be ever present in my house at that level. The RPA-1 does hum, but I need to be right next to it to hear it.
Anyway, those are my thoughts so far. I'll be contacting Emotiva about the power draw and hum on this unit.