I have had no problems with the rope plugs in more than ten thousand miles and would not hesitate to use one again if the hole size is appropriate. The last one that I had on my GSA was in Alexandria, LA when I was on a trip and finished up with over 2,000 miles on that trip alone plus several thousand more before changing that tire.
Went to James Bay Quebec with some FJR 1300 Yamaha guys and one of them had three plugs in his rear tire. He went several hundred miles at well over 100 mph with no problems.
Do start off easy and monitor the pressure. I have taken off tires with rope plugs that I installed and the rope from the inside appears to be fused and is not going to come out.
All things being equal I would rather start off on a trip with a fresh set of tires but these are what my experiences have been and for me I have no qualms.