I have the LW and don't find it stiff, but that's certainly a matter of getting used to it. Compared to a real organ with electric action that I played years ago, I find my keyboards much more comfortable. With the real organ, I had the feeling of falling through.
Basically, however, I like the LW better than the LF. When I bought my console, I tried both and was happy to pay the extra. However, after seven years, the rubber strips are worn out and I have to replace them (cost: about 200 euros for four manuals).