Our parents own Wyndham and we have stayed at Bonnet Creek (BC) quite a few times. TBH, if you don't care of being at a Disney resort, BC is definitely a better value. Its location is superb without paying the premium price.
We aren't DVC members (yet), but definitely looking and working on it. Even though staying at BC is much cheaper, the reason we want to buy DVC is simple - We just love Disney more!

We do non-park days every trip, so where we stay matters to us greatly. Not saying BC is not a great resort but it's just not for us, we don't enjoy our non-park days there. However, I will say this, in the future if we don't have enough DVC points to book our entire trip, we will definitely use BC to do split stay, and stay there during our park days. To us, that's still way better than staying in a regular hotel room off-property. Or if I want to stretch my DVC points, I would do our Fri-Sat stay at BC, then Sun-Thurs stay at DVC.
Deed Expiration - I think this should be a big part of deciding between the two. Someone please correct me if I'm wrong, Wyndham has no deed expiration? Ownership is in perpetuity I think? So that's something to think about if in 20 years you no longer want your contract, how easy is it to offload it? DVC is the opposite, every contract has a deed expiration.