Thanks, FB. I have one bike each, and was trying to think about any advantage searching out a threadless. I agree, they both work well. So, are these operative:
1) Slight weight advantage to threadless (pretty meaningless - if I raced I'd be in Cat 6 - baleine hors catégorie)
2) Slight strength/stiffness advantage to threadless (given my size - big frame - and weight - 240# this might be a slight advantage)
3) Better selection of CF threadless steer tube forks if I have to replace one (and if I find a 2000 frame with a CF fork, I'm replacing it).
4) Slightly easier maintenance, at least that's how it seems to me now.

I'm leaning towards grabbing the next good deal on a nice 853 frame I see in my size and going with it.