I have had an LPA-1 powering my system for about 9 months now. I am still as happy with the purchase as ever. It does a fantastic job at powering my system. There are few things that 'stir-the-pot' more than an amp debate, but I'm a believer that it does matter in certain cases. My receiver (Pioneer Elite VSX-43TX) was not rated to power 4-ohm speakers, and really couldn't do it. It would clip & strain at even moderately high volume when powering my M80's. The LPA-1 doesn't break a sweat.
I did have one minor problem with mine. A couple of months ago, when firing up my system, one of the blue LED channel lights didn't come on all the way. It stayed dim and sort of pulsed a bit. The channel was on and playing just fine. I tapped the front of the LPA with my knuckle and it came back on as normal. Hasn't done it again. I'm sure it was just a loose wire. If it does it again I'll call Emotiva. 5 year warranty, ya know. Other than that, it's been perfect.
I owned the LMC-1 for about 2 weeks and ended up returning it because it was just too buggy. This was way before the firmware upgrade, so it may be much better now. YMMV. That MMC-1 at $899 is a great price. Although the nearly legendary Outlaw 990 is also now $899. While I have heard neither, they are both supposedly excellent pre-processors for the price. Although both a little long-in-the-tooth and probably on sale for a reason. I expect we'll see some new models from both companies in 2008.
If I hadn't just bought myself a new laptop, I'd probably be buying either the MMC or 990 for myself this holiday season with these prices.
If/when my Pioneer dies, it will be replaced by a prepro from either Emotiva or Outlaw.