I have had both the AE-25 and MV-52 in my system for a few weeks at a time (the AE-25 in both triode and pentode mode). While using the AE-25 I had on hand the stock tube set as well as Svet KT-88, Svet EL-34, Bugle Boy 6922, and some random old 6CG7. The MV-52 I used had Sylvania big bottle 6CA7 outputs and GE NOS for the rest. I would take the MV-52 over the AE-25 any time. I think the AE-25 is way over rated (or maybe just requires unobtainable NOS outputs to work well). Having said that I currently own a Pass Aleph 3 amp that I choose while auditioning tube amps. For context I will list my system...
B&W Matrix 803sII
Pass Aleph 3
Audio Electronics AE-1 pre (same circuit as Cary SLP-98)
Meridian 506 cd player
Audio Electronics PH-1 phono stage
NAD 533 TT
MIT T2 interconnect
Synergistic Sig.#2 speaker wire
Hope this helps
B&W Matrix 803sII
Pass Aleph 3
Audio Electronics AE-1 pre (same circuit as Cary SLP-98)
Meridian 506 cd player
Audio Electronics PH-1 phono stage
NAD 533 TT
MIT T2 interconnect
Synergistic Sig.#2 speaker wire
Hope this helps