I was faced with the same choice. I took both units home and keep them for about a week. I thought the Monitor sounded good, but it was little too slow to go with my SL-3's. It drew too much attention to it's self. When I got the Depth home, I new I didn't need to look any farther. It integrates wonderfully, is very fast, and will go deep. I also trying the Descent, it is little better than the Depth, but I didn't feel like I needed it in my room (22 x 13 x 8.5). In a larger room maybe, but it's an extra grand. I have been very happy with the Depth for my two channel system, I have not tried for HT. I would guess the Monitor might be better for HT (more boom). I think they are both excellent subs, you will just have to listen and pick which one you like the best. I think you will be happy with either one. Good luck.