Pass Labs X2.5 or Krell KAV-280p? WWYD?

What would I do? I would buy the best tube preamp that I could afford.

Since you wish to limit yourself to SS though, I would look long and hard for a Klyne 7 series preamp. Hard to find on the used market, but when it comes to SS, hard to beat for the money. IMHO.

I have nothing against tubes per say, but I am spoiled by the features that solid state preamps offer in this price range. Remote control is a "must have" for me personally, balanced outputs, and 5 or 6 inputs, to get a tubed pre that has these features of the same quality as these units would most likely run into a substantial higher price. Same for the Klyne. I've heard the Klyne at the local salon, and it definitely is a fine piece of gear! But, they are not going to be selling anywhere near the price of these two pre's.  Maybe on my next preamp upgrade I can move into that price territory? 

Out of curiosity, what price range are you talking about?

It seems as if you are asking an awful lot from a preamp for a small amount of money. Especially if you are talking about a true differential design.

You may be able to get better quality by looking for an integrated amp in the lower price ranges (or even higher). Cost saving could be used on fewer chassis'/cords/cables instead of on lower quality internal components.

Especially since you are already saying that your amp is next on the list.
There are some very good integrated amps on the market these days.

That's just my $0.02.

The price of the two preamps I'm looking at are about $1500.  The reviews I've read on either of them are very positive. Of course they cost $4 K new, so, substantial depreciation there. I did look at an Audio Research tubed pre that has all the features I mentioned, but it was a full thousand bucks higher.  And you are right, I could probably get an intigrated amp for cheaper than separates. But these Legacy Focus speakers are power hungry monsters! I'm hoping for something like a 300wpc Krell or similar.  I'm even considering a D class amp for the sheer power they offer. 

I've thought about a tubed amp, perhaps a tubed intigrated, but if that was the route I was going to take, I'd do the whole thing different. With some smaller tube friendly speakers, perhaps in a smaller room. I might even build it all myself, with a Dynaco kit and speakers of my own design. But for now, I'm on the path of full scale system that can reach near realistic volume and dynamics. The fact is that if I move up from the Halo 3 to either of these preamps, I'm sure I will be blown away by the vast upgrade! So it's a win-win, I was just curious if anyone out there had any real preference for one over the other. I'm kind of leaning toward the Pass Labs just from reviews I've read. 
 
Another thing on my wish list is a Jolida tubed phono preamp, that may be the only tubes found in my setup, and could make a world of difference?