In my mind if you were going to the expense of replacing your primary winches with new ones, why would you get anything BUT self tailing? It would be silly to buy brand new winches and then put those Winchers on them!
I can get a pair of used two-speed, oversized primaries for $300-400. One self-tailer will be at least twice that, and it will probably be barely big enough. So it would be four times
more expensive to get self tailers, and possibly more.
That's the kind of price difference that makes you think twice.