Thanks for considering a Sundance 3700RLB. This model has been one of most popular models since its release several months ago. For some clarification on leveling; 6 point Electric Ground Control 3.0 is the only leveling available for this model (4 pt. is not sufficient enough per mfg/engineering suggestion).
There are differences between the GW 3800 and SD 3700, specifically the following; GW has optional King bed, residential refer option, 1 1/2 baths vs. 2 full in SD, High Gloss exterior standard, tank heaters, increased insulation, reclining furniture in LR, large bathtub vs. corner shower in SD and several more items which really separate the brands from each other. Feel free to visit our webpage or a brochure for further in-depth information. I hope this helps clarify a bit.