Agree with Drummerman, altho I don't believe they are a compromise betwen transistor and valve amps, just an in-between, of sorts.
When i replaced the Primare power amp with the Sugden Masterclass power amp, it sounded amazing: the clean, detailed sound, with lush midrange and amazing wide holographic soundstage, but at first it did indeed feel like some of the dynamics, range and power had gone. However, it took me only about an hour to get used to that, and switching back to the Primare sounded more artificial and "digital". Later I changed all (the rest of) the cabling over to Nordost, which complements Sugden perfectly, bringing in some extra excitement, evening out the balance, and with a leaner, tighter and deeper bass (there was plenty of bass without the Nordost, but a bit soft and more at the upper bass level).
Another great quality of Sugden (well, the Masterclass power amp), is that it reproduces the acoustics of a recording incredibly well - therefore on a good recording, the preformers seem more "in the room". It does indeed have one of the sweetest, grainless trebles, which is good for poor recordings and poor sources (like freeview).
So, I would say, yes go for it, as you will love it in the long run, but it's still (as always) worth auditioning before you buy.
... ahem ... great comparison ... just in case it escaped you, the fella is looking at amps around 1k not £3000. Oh, did I mention that it also sounded rather 'brittle' if I remember right?