I am running Bridgestones on my K bike right now because that's what the PO put on the bike right before I purchased it. Personally, I believe that you should run the best tires that your wallet will allow. If you can do better than Shinko, do it.
Years ago, I had a Shinko rear tire on my Yamaha XS 750 and it was a great tire for the money. That was about a decade back and they probably make a better quality tire today. If cash was tight, I would consider them for my brick. How much cheaper are they than the low cost Bridgestones?