I think its odd that REI doesn't use their brand of bikes on mountain bike excursions. They don't even use a brand they sale. The Grand Canyon trip says they are using Santa Cruz 5010s. REI doesn't even sale it. Seems like marketing in sales is not on the same page.
@drew2fast thanks for bringing this to our attention. On our REI Adventures cycling trips, we use a range of bike makes, models and styles that are well-suited to the style of riding and terrain you'll encounter on the trip. As an example, the Santa Cruz 5010 is a high-quality full suspension mountain bike that works very well for our Grand Canyon trips. That said, we regularly update our bike fleets and specific makes and models are consistently evaluated, and sometimes changed, to ensure we provide the best bike for each given adventure!
At REI, we believe a life outdoors is a life well-lived.