I've been using Hotels.com now for many years to find great deals on hotels. The system is easy to use, provides detailed information on each hotel, and generally finds the best deals I've seen from any other online booking site. I've never had an issue with my bookings. I've been able to change bookings without any hassle whatsoever. Not sure why the negative reviews here, but I've not had any bad experience using this service. I will say that I am not happy with the recent change to OneKey rewards program. Previously, you only needed to book 10 nights and then you'd receive one free night at the average cost you paid for those previous 10 nights. I just returned from a trip that was 10 days at an average of $175/night, and I have "OneKey cash" worth $40. It's really bad.