I'm currently running my KM140s straight into a stock HD-P2. While I'm mostly satisfied with this, I recognize that the last piece of the puzzle is an external pre-amp. For a while I've always thought that I would eventually buy a V3, but I know that not everybody considers the V3 to be worth the high price tag (for example, I've read that a lot of tapers don't like its ADC). So at this point I'm looking for recommendations for the right equipment to upgrade that part of my signal path. I know the UA5 is highly respected, so that option is on the table. I've also considered the MiniMe, and I even considered just having my HD-P2 modded. However, I'm not 100% certain that I will always have the HD-P2, so I'd rather not go that route. So I guess my questions would be:
1. For those of you familiar with the KM140s and HD-P2, is one of the pre-amps especially well-suited to stick between them? Are any of them not a great match?
2. I know the V3 comes as either 6V or 12V -- how does that difference manifest itself in the taping world?
3. I've seen some of the V3's in the Yard Sale advertised as "opti-mod" -- I'm assuming all V3's have coaxial digital out(?), which is all I could use the with the HD-P2 anyway. Or does the opti-mod accomplish more than just giving it an optical output?
I'd be happy to spend just a couple/few hundred dollars on a UA5 (or one of its modded forms) if that will significantly upgrade me, but my budget would eventually allow for a V3 if the consensus is that it's worth the extra $. Regarding mods - I often have a hard time conceptualizing the differences between the available mods, so feel free to try to teach me what I should expect transparent, presence, and warm mods on the UA5 (or available mods for any of the other pre-amps) to sound like with the KM140s.
Also, I'd be interested in any general advice you might have in trying to make a decision like this, and if there is any cautionary advice regarding the use of any particular pre-amp with my gear (from powering it, "hotness" of signal output, etc.).