You know, buying an RV is a real personal thing. We started with a Class A and I just didn't love it, so we found a C and I feel more comfortable driving it. I would suggest that you rent one first and see how you like it. You can find a lot of nearly new RVs for sale that folks thought they wanted and turned out they didn't
And that is my second suggestion - don't buy new. You can find some great bargains out there.
Are you going to need a tow vehicle? You can see a lot with an RV alone but there is a lot to say for finding a place to park and then having a car for exploring, shopping, sightseeing, etc. If that is the case, you might want to consider a 5th Wheel.
How much do you want to spend is also a consideration. Like I said earlier, if you can purchase a high end used for a cheaper new, go for the high end every time.