Well, it was an expensive gamble. They sound great, I love how light and small they are, but they just don't hang with the loud guitars and drums I play with the way my 410s do. If I wasn't playing metal, they would be great. They just can't replace my 410s. So I am disappointed. I was really hoping to downsize and give my back a break. They're great cabs, just not for me. Looks like I may be getting rid of them.
On another note, I really dig the MiBass 550. I haven't cranked it through my 410s, but I did tinker around through them and it sounds great.