Phono preamp suggestions

Does anyone have any experience with any of the following phono preamps:

Creek OBH-15
Musical Fidelity X-LP
Primare R-20
Pro-ject Tube Box SE II

I'm looking to buy a phono preamp second hand for use with a Pro-ject 6Perspex. The models I listed are all available used where I am (Japan).

For the cartridge I was thinking of either audio technica AT33EV or Ortofon Rondo Red, or an MM cartridge in a similar price range (Ortofon 2M black or bronze?). Frankly, I have no idea what kind of difference to expect between MC and MM, except perhaps that not all the preamps I listed will work as well with MC. (I am not interested in getting a separate step-up transformer.)
I have not heard any of the phono stages you list, so perhaps you should take my advice with a couple of grains of salt. I still have one to recommend if you can find it: the Moon LP3. It is a wildly musical device and its 100 ohm MC load setting ought to fit the AT33 very well. Yes, depending of course on the arm you own, I would go for the AT33. I own an AT33PTG myself and am really very happy with it.

MC carts used not to give you tracking as good as the best MMs, but that's pretty much a thing of the past now. MC cantilevers are often stiffer than MMs but the AT33 is an exception and you can use it in a less massive arm. MCs often have line contact stylii where MMs may not, and that's a dealmaker for me--I want the line contact stylus even before I choose MC or MM. Lastly, as far as music is concerned, expect an MC with a line contact stylus to give you refinement in the highs. If you are at all sensitive to HF distortion, plan to get an MC.
While I was shopping for a phono stage I was looking at most of the models you have listed but I decided to go with a Graham Slee Era Gold Mk V. One reason I did is becuase my dealer allowed me to take it home to demo before buying. I was looking at both tube and SS, too. I initially was interested in both a MM & MC capable stage; the Era Gold is MM & HO MC only. My cartridge is a HO Dynavector DV 20X. I am thrilled iwth the outcome especially compared to the onboard phono stage on my preamp.

Part of the magic is matching your phono stage to your cartridge which is where a reputable dealer comes into play. Let you ears make the decision for you. Best of luck.
The Pro-ject Tube Box SE II got an excellent review from HIFICRITIC, placing ahead of ones costing several times its price. I use the Dynavector 75, which is in the same price range and is extremely good.
It seems that neither Sim Audio nor Graham Slee are available here in Japan.

I heard the 6perspex with a denon mc cartridge and the tube box ii se in a shop the other day, and it sounded very nice. Unless someone can put in a good word for any of the other options I listed, I guess that is my safest option at this point (my budget will be busted unless I get the preamp second hand)
The Project one is fine, but for a much lower price you can get a Bellari VP129 that will better it (particularly in resolution of instrumental and vocal timbres), but it is MM only. It is almost always listed here for under $200, sometimes for much less than that. I would not go with the CEC, unless you want a really bright sound. Haven't heard the others on your list.