It really depends on the car.
I haven't even felt a need to try the 1 way diff in the HB D4 yet, the car has awesome steering. I have the centre 1 way, and at times have even locked that for no 1 way at all!
Still loads of steering
But from experience in the pred you win and loose on different areas of track. I had a prototype 1 way diff in at Ozfest couple of years ago when they had that silly woodern jump in front of the rostrum, it felt soooooo fast but I couldn't keep it in front driveshafts
I had to change to the std diff (with prop 1 way), the car felt slower but the lap times were identical. I could feel the car wasn't as good in a couple of hairpins, but it must have been better somewhere else.
G