Technically the spec is a bit stranger than that… It is if those devices on the same port are all talking to your computer at once that you get the slowdown. Now, if your mouse is 2.0 compliant, but only has the 12MBps speed, then you should be fine. USB is a weird spec in that way, but you should try testing it to see. I have used a USB 2.0 HD while using USB 1.1 devices even and while much slower than FireWire, it was fast enough for my file transfers. If you are doing something like video editing though, USB 2.0 spec really isn’t the greatest anyway. You will only notice the problem if you have a lot of USB 1.1 stuff working while trying to capture because you might get a dropped frame here and there, but if your buffer is big enough, you should be fine.