I was able to get a commercial policy through State Farm. $50(ish) per year for airframe coverage. I just couldn't add my UAS to my existing Personal Article Policy. I'll get liability coverage through Air Modo.
Yes, you're right if you're only insuring one or two items under the personal articles policy, they are inexpensive. What I find annoying with my carrier is that I have multiple policies with them. You'd think they wouldn't get upset over a $350...
Much prefer the EU and UK way, no commercial vs. rec. the system is based on risk. Everybody has to test and be certified based on where they want to fly.