I had such a hard time finding a strap-on harness that would fit well, be comfortable, and move with me while I'm thrusting. After checking out some really expensive harnesses at high-end sex stores, a friend who had this lent me hers, and I loved it. It's durable, easy to wash, and easily adjustable to fit different body types.
The dildos that came with the harness were a lot smaller than I expected, but would be good for beginner anal play. I just switched them out for larger dildos, which was easy to do.