I've been a Wyndham Diamond for a couple of years now and frankly I'm a bit disappointed, especially compared with ChoiceHotels where I am also a Diamond.
For starters, the front desk staff at Choice Hotels almost always acknowledge and thank me for my Diamond status. By comparison, the people working the various Wyndham front desks rarely ever mention it and to be honest, I don't think they care (or have been trained to care). I'm not a guy who needs to be fawned over, but the recognition is a nice touch for starters.
I say "for starters" because you are much more likely to be upgraded if the front desk staff care and are actually aware of your status and its commensurate perks.
At most Wyndham properties, you definitely have to ask to be upgraded and judging by the response I've often gotten to this request, it would seem that a lot of the front desk staff are unaware of it, and as such less likely to provide it. Typically Wyndham's higher end hotels (Wyndham Grand, Wyndham and Wyndham Garden) are better on this.
At ChoiceHotels, as a Diamond I have arrived to find that I have already been upgraded by the time I check in on a number of occasions.
Finally, on the whole I find ChoiceHotels properties - especially Comfort Suites, Quality Inn & Suites and Sleep Inns to be of a consistently higher standard than comparable Wyndham properties.
ChoiceHotels may cost a bit more on average, but the overall quality in both rooms, service and perks is worth the extra cost. Plus, I like the 60% point bonus I get as a Diamond.
Wyndham Hotels offers better deals on award nights.
I will go out of my way to maintain Diamond status with ChoiceHotels because they do more make it worth it to me. At the same time, although Diamond status doesn't really mean much with Wyndham, the program does offer a good variety of affordable options - especially when booking award nights. I'll continue to use them but as a Diamond level traveler in both programs, my preference is definitely ChoiceHotels.