It's very good that old ICBMs are being converted into space launchers. Among other things, we get to know some data on ICBM reliability.
Kosmotras, which markets SS-18-based Dnepr space launcher, making a presentation at the Paris air show put reliability of SS-18 at 97% in more than 160 launches (this includes the four space launches conducted so far). This number must include launches of all SS-18 modifications, from R-36M to R-36MUTTH to R-36M2, since it is highly unlikely that it refers to the R-36M2 modification only - there were just about 50 R-36M2 missiles deployed, so there is no way 160 of these missiles were flight tested.
Since SS-18/R-36M is a relatively new missile, its success rate is higher than the overall average success rate for Soviet ICBMs, which stands at about 92%.