I was a stickler for sharp as a tack photos before I ventured into ULF photography. I'm, thankfully, able to see the beauty of selective softness now though. I like both of the images, but if I were to purchase one to hang on the wall, it'd be the soft one; it is more accessible and slightly abstract. It's more universal because it's no longer just about the waterfall, but showing the photographer's hand in making the image.
I like them both but I much prefer the one shot with the 150 Symmar. I like the textural contrast between the soft water and the hard edginess of the rocks. I also like the wide perspective that places the waterfall as part of the setting rather than dominating it. I seldom prefer SF, BTW. At any rate, both are beauties.