Bold for you, just like the others are doing!
I used hotwire for a one night hotel stay, and I used it for a car rental. We didn't do a one way rental though, we got it from and returned it to LAX. We got a rate we were happy with with the car, and a rate at the hotel that was decent. We had Motel6 booked, through hotels.com, for somewhere between 50 and 60 bucks, and got the Hilton (through hotwire) for just over the rate at Motel6. Alas, Hilton does have a hefty parking fee, but it was still nice to stay at the Hilton instead of Motel6.
I absolutely urge you to study betterbidding.com! Awesome site. But you want to delve deep into it, make it your job for the next week to study it. It can help you figure out, to a good extent, what hotel you might be about to get, from the description/amenities/location. That can help b/c you can go to the hotels' sites (from the ones you think it might be...for instance, I knew the hotel I was about to get was either the Hyatt or Hilton) and find out about resort/parking fees ahead of time, instead of being surprised later on.
Now...airfare...there's not much benefit in booking that through those sites.
Oh, I wanted to mention that I also have used Expedia and Orbitz...
Anyway, they generally have the same rate as the airlines do directly. Right now most of them are dropping their booking fees, at least on some flights. If the rates on the site and the airline sites are the same, be SURE you're not going to be charged a booking fee, b/c then you're paying more for the same product, and really it's not even the same, because now you have a
travel agent to contact instead of contacting the airline directly!
On our last trip, hubby and son had Alaska credit, so I booked their flights directly through Alaska's site. I had no credit, there were no booking fees, the prices were the same, and I could get credit through a rewards site I do, so I booked with travelocity (I think). If there had been a booking fee, I would not have done that, b/c booking fees bug me.
I used Orbitz for a hotel stay once, and didn't realize there was a booking fee until it was too late. They made the cancellation time further out than the hotel itself, so when the HoJo Entertainment Book rate came out, I coudln't cancel the Carousel (it was only a one night stay, so being charged one night for canceling too late would have been silly). Disappointing.
Just take the time to really study the sites, see what you're getting. Get the cancel policies, get the phone numbers, etc etc, and book with knowledge!