I have the Flaming River kit on my car and I don't mind it at all. What I like about it is making things simpler, less components, no more pump whine, no more drag on the belt, and cleaned up the engine bay. I have 3.5" Welds up front, which helps turning I know.
At a dead stop: have to use both hands and use some muscle.
At a slow speed: still have to use both hands, but much easier
At higher speeds: feels just like power steering
I really like the feel of it. You feel more through the wheel than with power (more precise)and once you've made a turn you can just let go of the wheel and it will snap right back straight... no need to turn the wheel to straighten up.
A friend of mine just got it too and he has 2000 GT wheels (17"x9" I believe) and he described it as being pretty much like mine. I haven't driven it, but he described the same things I just did. The only time you'll be grunting and groaning is at a dead stop. The main thing is... Flaming River manual steering IS alot easier to stear than a power rack with the pump removed and the lines capped off. Or like if you have power steering and you try to turn the wheel while the car is off.... manual steering is ALOT easier to turn than that.
But the only car I've actually driven with manual steering is mine with the 3.5" fronts, so maybe someone who's driven it with bigger wheels will chime in.
Hope this helps!