Why would you want to stay off-strip?
I can't comment on the resorts off the strip. I made the mistake of staying off-strip once, and have since ignored all off-strip resorts. There is so much to do in Vegas and having the rare opportunity on a vacation to walk to all the best the destination offers is a treat too great to pass up.
Even if you want to visit regional attractions and don't want to gamble a penny, staying on the strip has many advantages. You can take short walks to some of the best restaurants in America. There are designer shops in every direction within walking distance. Shows, the good, the bad, and the ugly, are also within walking distance. If you like nightlife, you will find stunning clubs in most of the major casinos.
I just like walking the strip for people watching and admiring the over-the-top architecture. Even though I have done it dozens of times before, I still enjoy walking the strip from Treasure Island to MGM almost every day of every visit to Vegas. It is great exercise and there are always new buildings and, of course, different people to watch every visit, even though I visit Vegas twice a year, primarily for business.
Why would you want to stay off strip and have to pile into a car every time you wanted to enjoy Las Vegas' best? Consider the Hilton Flamingo, the Marriott, or one of the lesser timeshares on the strip.
If you want to impress your guests, stay on the strip. Otherwise, regardless of the quality of the off-strip resort, you may find your guests disappointed when they realize all the best is close, yet so far away!
P.S. For those who may have read my Hawaii posts and find it incomprehensible that you find me reveling in fine dining, shopping, nightlife, etc., understand that I get my fix for such things in Vegas where they are at their best and consider such options in Hawaii not even third rate in comparison… so I figure, why bother. Rather, I go to Hawaii for what Hawaii offers in incomparable quality, her lavish natural beauty.