I'm giving this the top rating because it's way more than I expected for the price. Most of the bad reviews are from people comparing this to the nicer hotels and casinos on the strip. Not a fair comparison. It's a great 3-star hotel off the main part of the strip.
Staff: The staff here are super friendly, from the woman greeting me at the front desk to the guy who unlocked my room safe.
Room: Clean, nice, modern. Nothing fancy. Ask for the Monaco Tower. Other rooms are apparently older.
Location: Perfect if you're going to CES since it backs onto the LVCC parking lot. Literally a 6-minute walk from my room to the conference center. Others on the main strip had to wait for shuttles, pay for cabs, and fight through traffic. It's also a $6 cab ride to the Wynn or a relatively safe 20 minute walk.
Casino: Looks lame but that's not part of my review. Just talking about a cheap, safe, clean, convenient place to stay.
If you're coming to Vegas for CES or anything at the LVCC, the Riviera is perfect. If you're coming to lounge around at your hotel then you'll probably want to pay the extra $$$ and stay on the main part of the strip.