My 2004 Lance came with a generac,( it was the last year for them, switched to Onan), I would exercise it each month for 1/2 hour, never used it too much camping, but it went bad with 25 hours on it. 3600LP, costed me 1500 to fix it, ran good and probably still running, but I sold the camper, I would run from a generac now, my 5th wheel has an Onan and it's quite and works great.
I had a Lance 821, 4,000lbs loaded and I now have a LiteCraft and I'm guessing 2000lbs loaded, at 75mph I got about 10mpg with the Lance on and with the LiteCraft I get 14mpg, the lower profile helps a lot I'm sure, but the weight difference is probably the big difference.
Camping at Pueblo State Park last week, first time in cold weather in my new to me LiteCraft, been missing my Lance the last few years, so I picked this up this fall.
I just pull the side pins and left the head off still attached to the king pin, It has worked the best for me, no more re-positioning to take the stress off and to hook back up is easy, I use the magnetic telescoping rods and put one on the pin slot and the head bolt and back right into the rods, lower and place the pins back in, most time perfect on the first try.