Just did something similar. It was a toss up between a new Coleman 274BH or a 2 year old 274BH. The new one was the same price as the used, but not an apples to apples comparison as the used has the winter package (Kodiak I think) where the floor and walls are insulated, along with heated tanks. I looked it up on NADA, and the asking price was right in the middle of the low to high range, and I negotiated it down $1000.
Trade off, no factory warranty, but got an extended warranty that covers all mechanicals for the next 4 years, and those are the important things. Since it is used, there is also no transportation fee, which saves another $1000. Since it is purchased out of state, the book price is lower than new MSRP, so I will owe fewer taxes in my lousy state.
On the plus side, everything works as it should, there is practically no wear at all on it, well kept, only the tires show that it is used, it was kept indoors when not used. It has extras that would have cost much more on a new one, which saves me even more in the end.
So think about more than just the OTD price, you also have added fees on the new one, higher taxes on the new one, etc. They have to list book value for tax reasons(stupid taxes) and this one came out to over $20K, the new one listed at just over $17K, so I got $3k in options on the used one, that I wouldn't get on the new one. If warranty is a concern, get the extended warranty for 4 years on it, at least get the peace of mind that if something breaks in the next 4 years, you wont have huge out of pocket expenses, such as having to replace the Refer or AC, or furnace. Any one of those is a big ticket item. Is it worth it? Some say yes, some say no. I personally have had them both pay off, or go to waste, but you buy car insurance and never use it(hopefully) right? It's basically the same thing.