OK, I gave this a "once-through" in my car and will hopefully be able to listen in a quieter environment this weekend.
You're right, this is really a very good M8. The tenor is very good -- if not quite at the level of Kollo (Solti) or Grobe (Kubelik). All of the female cast is good -- particularly the Mater Gloriosa (she sounds truly heavenly). The bass singer is probably the weak link here, but he is at least acceptable. There is quite a bit of orchestral transparency and inner detail (especially woodwinds). The organ is superb. Ashkenazy conducts with good flow and expertly handles transitions. My only complaint is with lack of presence of the percussion section and the special purpose instruments (mandolin, etc.) -- but ONLY in comparison to the Inbal/Tokyo recording which is imply unmatched in that category. I would likewise have preferred more tam-tam presence at the end.
I hate to make proclamations after one listening session (especially one done in my car), but this is probably an easy first tier choice for me. I still prefer the Inbal/Tokyo to all comers (I practically listen to it weekly), but the Ashkenazy has a lot going for it (singing is undoubtedly better, much better organ).
Barry: I know you don't like how Inbal handles the section in Part II for high strings, harmonium, and harps (too fast for your taste), but I think it works just fine - especially given the overall faster tempi of the performance. Although none of Inbal's singers are anything special, the recording has the "extra benefit" of the soloists being recorded fairly low in the mix -- which also explains why there is so much orchestral detail in that one.