I don't think nopCommerce team is just listing some partners because they are being paid. nopCommerce team validates their partners (including hosting partners) with their own parameters (obviously they are not published except a few here
I can say that because we've recently faced a month long outage with A2Hosting which was one of recommended hostings. Now you won't find it in the list, because nopCommerce team has removed it because they failed in one of the most important parameters. So even though they were paid partners, they are not there anymore.
Your experience with SmarterAsp may have been one OFF experience. I think you should contact them as they have really good support and we use them for a few of our client sites and we never faced any issue.