I'm biased by being a big fan of the WM and not having been to the Conrad, but I'd still suggest sticking with the WM. I doubt that they'll look down their noses at you. I would hope and think that once you arrive, you'll be treated like any other guest. (You might want to reconfirm that you'll get whatever HH perks you're entitled to there.)

Also, whether to switch also could hinge on what kind of room you've booked. If you've booked the most basic room at the WM, for instance, you'll be in a very nice over-the-water villa. At the Conrad, you'll be in a beach villa, which IMHO doesn't compare as it's not over-the-water, is less private, I believe has adjoining walls with neighboring units, etc. Plus you'll have to be careful and do some research re which Conrad beach villa they put you in, as I've read some complaints about some locations being noisy. Plus the WM is a smaller, more intimate place.

The only caveat here is that if you're huge snorkeling fans then the Conrad is better. But unless that consideration drives your planning, I'd enjoy the WM while you still can as an HH member.