I was with Miller and had National Interstate also. So I ended up with Geico on my truck and Progressive for my fiver (I full time) when I had to renew this past July. Progressive was more expensive then Geico for my truck.
I had a long email conversation with Geico asking about full-timer's insurance. All of their replies danced around the question without giving me a firm reply that they did indeeed offer it, even though I asked diectly - 'Do you offer full-timer's insurance'. I am pretty sure the real answer is 'no'.