Best 'Grand Canyon' tour?

[Viper_Larry]

As usual, search not really helping. We're going to Las Vegas next April and my sister wants to visit the Grand Canyon. We've done it before in a plane flight day trip but they want a bit longer to ride horses on the rim, etc.

Any recommended tours people have been on? They will only be in LV for 5 days, so max 2 day trip to the GC and definitely fly.