Describing the difference between the 1096 and 1099 is difficult. It seems odd to me to say its an $80 difference. Cause if this was a commercial product it's be a $500 difference. So I think of it as a 30% difference in price. "Downgrading" to the 1096 keeps the detail, clarity, imaging, etc as is expected out of the mids and tweeter. The lower midrange and upper bass is what changes. And that change is 3db from 80 to 600hz in the words of an engineer. In the subjective sense, it's going to be a little leaner (not as full), not take quite the hammering the 99 does. It also doesn't have the vertical directivity of the 99, which is quite nice.
My comments on the differences back when I evaluated them are back in this thread somewhere. They were brief but I was surprised how similar they are. The biggest thing was it just couldn't quite breeze through complex bass the way the 99 could. It's was much more subtle than I expected. The fact that the same XO worked was really sweet. Or I'm not sure we'd be having this conversation. I would have still done it. But Erich would have had to stock essentially two different speakers, that are essentially the same speaker. Doesn't make sense. So that was nice.
If I had to pick, no question the 1099 is better. But if the space constraints dictate, then its a very flexible speaker for narrower center, shorter, cheaper, etc.