Yeah , the first two lathes I had were change wheels for threads and feed speed, can be a bit tedious. It's worth checking if they have the change wheels with it.Hard to argue, but I'd still suggest getting one as large as you can for the money you are willing to spend (bearing in mind that at the lower end of the market bigger is usually cheaper!).
And buying one without screwcutting abilities almost certainly means replacing it a few years down the line.
It would look a bit like this (a pile of gears) but probably a bit bigger.
just try and get a decent second hand one at the right price .not some old worn out one .theres no such thing as buying one to learn on unless its going for next to nothing and you cant afford better![]()
What you says is true , expect more searching, fettling and buffing time for an older lathe. If you have the dosh a nice shiny new one is amazing.

Stu