Randy, yes I shoot with the AF-S II 400 f/2.8 on the D3 or D300 and use the MH-01 on a 680B monopod. The MH-01 is so well-made and strong, and the vertical tilt works very well.
I use my AF-S 400mm f/2.8 on my monopod with a 3232 swivel and a RRS clamp.
A very practical combo that works very well in my opinion. The vertical operation is fine (which is why I got a 3232 in the first place).
I will mostly use my tripod with the 400/2.8 - it is a pretty heavy combination with the D2x. But sometimes a monopod is more practical because of needed mobility. I would not want to be without the vertical swivel on it.
I've used my 400 2.8 on a pod for almost 10 years now. Tried the 3232 head w/RRS clamp for a year shooting the NFL. Gave it a good year long work out then went back to the straight RRS lever clamp. I ordered/received the MH-01 and used it at the 1st preseason game. Can we say day and night difference between it and the 3232. You won't regret it. But do order the lens plate from RRS. It provides a lower profile. The plate/grip that comes with the lens puts the lens SO high that it seems very unstable.
I use the 486RC II with the 300 f/2.8 but have wanted to upgrade it anyway, would prefer something with a little more precise control on the tension...have heard you can get that with the hydrolic type of ball heads.
Anyway, congrats on the 400 something I am seriously looking for. That beach camera price is nice, perhaps I don't need to wait for a used AFS-II
I was hoping a lot of 400 f/2.8 owners would "upgrade" to the new version and sell their old ones for 5k and under.
I saw one, and did not hop on it at KEH for 4200. Went back to grab it a few hours after seeing it and it was already snagged up.