With elevons it flies ok but nowhere near as good as aileron/elevators.
With elevons, when you make hard turns that require a lot of elevator trim, and you dial in some "aileron", you loose "up" trim.

If you want to make 4 point rolls with elevons, it will be very difficult to maintain altitude since you will loose elevator trim as soon as you dial in "aileron".

I am 300% behind separate controls. I have flown F-16's many times so I can clearily tell the difference. Some people may say that tailerons behave better during crosswinds. Nope, both fly just as good as you can expect.

However, if simplicity is more important to you, or you don't care too much about precision, tailerons is still a very viable option.

My advise: keep whatever setup comes stock with your kit. Not worth the effort to change it to either configuration.
These are some of my F-16's, both aileron and taileron: (The Cermark with the Edwards schem has been the most fun so far, doesn't get any simpler than that!!)