Although many of use consider the name Winnibego sinoninimous with Class A MHs, I personally have never been overly impressed by their quality. I my opinion, their are several other manufaturers that make products that give a better bang for the buck. The first one that comes to my mind is the Fleetwood Bounder. These are very solid MHs with very family friendly layout.
One complaint that I have with Winnibego is that fact that many of their parts can only be replaced with Winnibego parts. This can be a bit of an issue when out in the middle of nowhere.
As far as Diesel vs gas is concerned, I have owned a Triple E Gas/Proane Conversion, Fleetwood Discovery DP and a Berkshire DP... now that I have had DP I would never go back to gasoline.
Upside of Deisel
Much more substantial chassis resulting in better ride ... particularily in wind
Air Brakes and Jake Brake giving much better stopping power
Much more power (torque) ... better to towing and climbing hills
Higher initial cost
Higher maintenance cost
We currently use our MH about 40 nights per year and feel that the extra cost is well worth it