Here is what I am discovering with the 1800, and it is only when needing all 16. You get 10 inputs that you can control gain. If you add a SPDIF interface (I added an Art pre-amp with SPDIF out, gives you 12. The other 4 inputs will require some sort of "gained" input. My only issue with the 1800 is, if you want 16 and you are going to use microphones, you need 16 pre-amps.
Right now and this is on the cheap, I spent 270 for the until. 60 for a preamp and then looks like another 100 for one more preamp (A cheap Nady is what I am looking at). So, 430, plus three rack spaces. This gives the ability to use all 16 inputs at once with microphones.
I used the 1800 a couple of days back, full band tracking on a low powered laptop and had no issues (this computer is just for recording). I was not concerned with latency as the monitoring was done live. I had no drop outs, everything recorded just fine.
Hope this helps.