The Sprinter based LTV Spirit SS is really nice. But, remember that with the slideout your mid section bed isn't as big as the rear electric fold down units in Sprinters such as ours. But you get a better bathroom and more storage. Even with the extra weight of the slideout you should be able to tow a toad of reasonable size--if rated at 5000 lbs one has to add the vehicle load and the weight of the vehicle. The dealer can help you. I am not that familiar with the Winnebago ERA 70C but it looks quite nice too. Probably cheaper but one has to compare the interior fit and finish.
cheers
Al