Rented a 25 footer that had electrical difficulties on three occasions over a ten day trip.  Luckily their help desk personnel were fabulous in getting a service technician out to remote national parks to try to fix the problem.  Unfortunately the rig had been improperly serviced before and the problem persisted.  It was disappointing the rig was put on the road but once we got the battery problem solved our experience was quite good.  I would rent again but would try to get a newer vehicle (ours had 98,000 miles) and try to verify the condition.