I have the 8900 (been a New Home/Janome girl since my 1968 used one)
If I had to do it again, I'd get the 8200, I do not need all those stitches
Otherwise I think they are the same machine.
Janome is really generous in taking in used machines too which will reduce the overall price.
I had a 6600, total workhorse, probably the best standard machine they ever made, but sold it last year, downsizing the herd. I bought it for use when I was away from home for 3 years taking care of my father in law.