Just got the lens yesterday, and it seems more than a little decent. Here are a couple of test shots (edited -- just as I would edit any of my photos -- not doing a lens test, per se, but a "is it a good lens for my photography" test):
All taken at f/1.4, since that's likely going to be the most used aperture, as I'll opt for the convenience of a zoom for wider apertures, even if the IQ of the prime is "higher". I chose it over the RF 50 / 1.2L, which I could have gotten used for about the same price, because I thought the smaller size and weight, along with the faster AF, would work out better for me than the extra 1/3 stop and possibly even "higher IQ" stop-for-stop. The IQ of this lens seems to be easily enough for me!