I agonized over this a lot. I had to get a new amp for my Forte 3 and Naim was one of the options. The various responses on this topic were that it is not a particular happy pairing, but I did not hear it for myself, I couldn't get one in for demo.
I owned until now a NuPrime IDA-8 (great amp, loved it with the Forte 3, but it digitizes the analog input and my OCD was not OK with it), Musical Paradise MP301 MK3 (inexpensive low power tube SET, very good value).
I got now a PrimaLuna EVO 200 integrated and it is just another level, honestly it is just no comparison, the realism, dynamics, bass, everything blows my mind.
I was not a tube guy, but oh boy, if you think about Klipsch Forte 3 and don't have a hard reason to not consider tubes, do yourself a favour and hear them with a PrimaLuna.