There are a couple of Class C manufacturers that are considered "best". Lazy Days and Phoenix Cruisers as I recall. Winnebago and Jayco are also considered good brands, there are others. Most major brands offer "entry level" and higher grade rigs, some with gas engines, some with diesel power. I don't know of any detailed unbiased reviews ranking best workmanship, best features/amenities, and best dealer after-sale support. Try googling "best brands of Class C RV's".
We own a 2004 Fleetwood Tioga 26Q bought new in 2003.I consider our rig of average housebox workmanship quality. We have replaced the fridge, roof AC unit, and the converter/charger and recently had the generator fuel system serviced and replaced the dual house batteries. Fleetwood Class C's are very common and many are used by rental companies. Do your homework and read advice on picking a rig that is best for you and your budget.