Also had National General (previously GMAC via Good Sam) until this year. No complaints but then didn't have any claims. Did like the idea I could turn the coverage on and off when in storage with a phone call. Went from full coverage to fire an theft with appropriate refund for difference in price.
BUT, this year I got a 20% increase in premium, with no issues on my end. Called Nat Gen and was told it was just the cost of doing business in Oregon. Told them not acceptable and was told "gee sorry to lose you as a customer, anything else I can do today." Attitude seemed that they didn't seem to much care.
Called around and went with Nationwide. Good help from agent and bundled significant coverages all via Nationwide.
I only price check about every 3 or 4 years unless something unusual happens. When I do price check it always amazes me the poor service I get just trying to get a quote. This time around I actually told The Hartford (via AARP) that I'd take their quote. Sent me all the info, policies, etc. Then about a week later I got a letter from them that they don't cover rental houses and I'd have to find someone else to cover it. Fortunately when I price check I start at least a month prior to current policy expiration. Called The Hartford back told them to not issue the coverages and then went with Nationwide. So far knowledge, help, pricing, and customer service have been very good.