I bought a set of these used. I really dig them so far. They have been on my bass for a couple of weeks now, but I haven't gotten to gig on them much yet due to a theater run where I am played bass guitar exclusively. I have an unamped gig with a drummer and pianist this Saturday, I will try to report back afterward.
They feel great on my left hand, and the E and A sound really nice on my bass. I have not had low tension strings before, and it is interesting. My bass was pretty powerful with spiros, but sounded unbalanced, especially in regards to volume on the E and A. I like to pizz hard at times, and the any E string I have used would bottom out on me from time to time. I don't have that problem (at least, not yet). The D and G are not bad, either, but they are kind of noisy. I can hear the plastic covering when I pluck and when I shift. Not sure how much this matters, but I can definitely hear it and might be an issue with recording.
My slapping is functional at best, but if slap is your thing than I would highly recommend trying these.
I am a decent arco player, but have to try hard to keep the d and g from sounding anything other than awful. They definitely have a PC arco vibe, but it is a little different.
These strings hold tune pretty well. Granted they were used, but I don't believe they were used long. Mine started to hold tune fairly well after only a few days, even in southern US humidity.
All in all, I want to give these strings a good run for a few months. If I had any arco heavy gigs coming up these would definitely be coming off, but I don't. I am hoping they will continue to break in, and perhaps the more I work with them arco the better they will sound.