VTL TL2.5preamp worth buying?

I have seen them for $800 in Audiogon and if the rave reviews are correct, I bet it would be a steal. My biggest problem with VTL is that their stuff breaks, it can be a pain if it happens to you. You should probably go for it for that price.
It would probably sound very nice.

I had a VTL Deluxe pre amp and it was very detailed and easy to listen to (12 years ago)

Certainly worth an audition. Intoxicating mids & highs especially on string instruments. Ultimately I decided agains ownership as it had more tube rush noise (in my system) than I wanted to tolerate.

I concur with Alex: the 2.5 was noisy & microphonic, but then so was the 5.5 for that matter. Typical for tubes, but still might be worth a try; some people do like these pre's.

I am using the VTL 2.5 with my Aleph 3 with excellent results. Very quiet, great sounding overall, well worth the money.

Yes it is. As does with almost all tube gear, you will experience a bit of tube "rush", especially with very efficient speakers. Once the music is playing, it is a non-factor. The use of some quality NOS tubes (I've used Mullards and Telefunkens), will quiet the preamp a bit...VTL doesn't condone this practice, however.