Ok. Time for my full review.
Let me start by saying that I'm really glad that I waited an extra night to post this, because my thoughts have swung a full 180 degrees thoughout this process.
The case for Hafler:
I've had the Hafler DH-220 for about 4 months now. It's a good little amp, rated at at 115 watts into 8ohms. The Hafler is capable of driving my 1Cs to pretty high volume levels, but doesn't bring a whole lot of bass to the table. It seems to image well, and has a pretty cleans sound. If I had to characterize it, I'd say that it's a little forward in the tweeter range, solid in the middle and a little light on bass.
My impressions of the TFM-25:
This amp can really bring the rain! I basically can't find the end of the volume dial on it, which is great but totally unnecessary. The 25 seems pretty clean also. It definately digs a lot deeper than the Hafler, which is something that I'm really looking for in a new amp. With the Carver, I 'feel' the music a lot more, even at .5watt on the meter!
On the flip side, I feel like the Carver is a lot more laid back on the high end... almost more-so than I'd like it to be. On some recordings I feel like I lose the vocals behind the rest of the music a bit.
The sound-stage with the Carver amp also isn't quite as wide. For this I kept going back to same track over and over again.
"Turn the Page" - Garage Inc. - Metallica
The intro begins with a guitar at stage center playing low, and is followed by another electric note played high and to the right.
With the Hafler amp, the second guitar is placed high and about a foot in front of the speaker. With the Carver it's still equally high but only as far right and forward as the speaker. However, in other recordings the stage has seemed quite wide.
I think the difference overall comes back to the presence of the high-notes. With the Hafler, the highs are much more forward than with the Carver and that manifests itself in the perception of depth and width in the soundstage at times.
I also noticed a few other sticking points about this Hafler amp and this Carver amp in particular. With the Hafler, I get an audible 'thump' when I turn on the unit, which is rather annoying. Also the power switch on the Hafler is backlit, but the light flickers constantly as the amp runs. I've looked at a lot of sources online that all say that it's basically normal for these amps to do that. There is a mod available to fix it.
With the Carver, I noticed that if I fire up the amp with the source and pre already going, I get a few seconds of really horrible distortion. The first time that this happened I thought I had something messed up in my hookups, but it happens everytime I start the Carver up from cold. I'm assuming that this is a sign of aging electronic components.
I also should mention that like every other normal MOSFET amp, you could cook an egg on the Hafler amp after about 15 minutes of music, whereas the Carver seems to stay cool no matter what I throw at it.
All-in-all, I like the TFM-25 amp. I think it's an improvement for the most part over my Hafler, although it does have its drawbacks as well.