I have the 9200D and it's a fantastic machine. I know Angelphie also has that one because she showed me all the extra things I had no idea it could do XD
It's all manual knob twiddling, but that just means you need to learn how it works which can only be a good thing. There are more expensive ones that have automated processes e.g. Janome does one with auto threading (Cosplex has that one), but in terms of stitches and hem types they do the same thing at the end of the day, you may just need to stick a different foot on.
I also have a friend with a Juki overlocker which she loves. These are meant to be industrial standard tech sized for the home, so they cost a bit more, but they'll also last much longer (though you won't notice the benefit of that unless you use it most days).
Ultimately the main brands are all suitable for casual costume making and it just comes down to picking one in your price range that does the things you need it for, best not to get carried away with how much fancy stuff it could do that you'll never use.
Most importantly try before you buy. Get into the store, give them a go and you'll find out if you're comfortable with it. You can certainly do this in Jon Lewis. Good luck
