UPDATE -
I'm upgrading this place from 1 to 3 stars because after all the ridiculous crap we had to go through (see previous review about nothing working and no hot water), they did get us into a new room right away and it was great. The new room was perfect, spacious and so very clean. The staff at the pool are VERY nice and we had a great time. If you already have a timeshare with Diamond Resorts, it's acceptable. If you're paying for it as a hotel, try another place.
I wouldn't say this has everything to do with Diamond Resorts because I've stayed at other locations (most recently, Polo Towers in Las Vegas) and it was amazing. I just think the front desk staff at this particular Scottsdale location needs some retraining.