Right now im using these on the kicker on my 45 degree wall, and they are really good for starting foot holds. Even on the vertical kicker, you need to focus our your foot will slip, but if you focus, they are rock solid. I also have a vertical section of wall, T'ing off my 45, and I use these for very technical climbing (side and under cling with crimps) and with poor handholds, and not using the nubs, they make a good v4-v5 route.
I've used a few of the bigger ones, with big nubs, on the 45 degree wall, and they are a good compliment with a good hand hold to make that hand hold a little less good.
Overall - a good set to add that is versatile and good value.