I am going to be the spoiler on this. Couple of years back while wheeling JV, my assist cylinder took a dump on me. I took it off and plugged the box. With stock power steering and a PSC pump I would say the stock PS performed about twenty five percent better then it did with the stock pump, this was with the ARB turned on or off.
So in my opinion, yes your steering will work better with a high output, high pressure pump.
If you have ever wheeled Johnson Valley (Hammers) you know you need all the help you can get.