Probably better to upgrade within the Naim world. If your 250 is getting on to 10 years old, a recapping will provide a very noticeable upgrade. Given that you already have a Supercap, upgrading your 82 to a 52 (if you can find one) would improve your hifi musically more than a change of power amp. I'm assuming that all your Naim gear is from the "olive" era, so another possible avenue is to consider starting an upgrade path with the current line. This is a path that I followed and I've never regretted it. Good luck and good listening.
Amp for Naim line?
I am trying to upgrade my amp Naim NAC250 for component which would match my other Naim top notch gear CDS2/XPS/NAC82/SUPERCAP modified by Whest and Tannoy TD12.Please advice.Oh and I know that I should be able to use non Naim amp to Naim preamp unlike viceversa.