While not an exact answer to your question (because I honestly don't know), I would like to offer a couple of things for your consideration.
Most people prefer fewer antennas, so consequently most radios are made to cater to them. That means those of us who want separate antennas are the ones stuck buying a duplexer instead of them. Duplexers are cheap because so many people use them specifically for this purpose. Consequently, I would very definitely choose my transceiver based upon more important criteria (like functions, features, frequency range, power, size, etc...) than how many SO-239s it has on the back. I think you'll be happier with your choice that way.
Good luck!