for those wondering, the 185 is basically an updated 99, which is the 3/4 version of the 66. So it has a drop in bobbin instead of a bobbin case.
As others have said, that is a very good price for a FW.
If portability is not a main factor, I'd lean towards the 185. All of the FW I've sewn on are rather slow, and I like having a bit more space under the arm. They are also more prone to jamming and having problems if you get any thread stuck around the bobbin case. And if you need to replace the bobbin case, you may end up spending near what you paid for the machine.