You are likely to spend substantially less time getting repairs done with a 10 YO DP then you will if you buy new. To clarify, if it's new, you are going to want every little thing fixed while still under warranty and this will take a great deal of time and effort since you don't want to throw away that extra 100,000, 200,000 or more, you paid to get something new. The used coach will have either no warranty or a brief warranty and you can focus on critical issues immediately after purchase and then simply get on with your awesome RV life.
I bought a '88 coach in '99. Yep, 11 years old and the dealer offered ZERO warranty. However, we were able to spend a couple of nights at the dealers RV park and they repaired every issue we found without question.
You need to find a well respected dealer is you plan to buy used or you have to have a professional inspect the unit prior to purchase if you make a private purchase. No matter what, don't look back. You did what you did and you have what you have. Whining will not help but the issues (if you did your homework) are likely not so bad and can be dealt with as demand requires.