Tough call. Their being on the rocks is not good news, certainly, but it doesn't absolutely mean that folks with their ERS plan are out of luck. If it comes to a bankruptcy, some other travel club may purchase the ERS and continue the service. Or, they may not...
I have had the Camping World ERS plan (also Affinity) for several years now, and have been very pleased. I have had to use it twice, and both times it was quick, painless and free. I have no experience with other companies, but just from hearing scuttlebutt around, I opted for the Affinity plan over the competition. No regrets ... yet.