One of the tire makers, Dunlop I believe, says if you run a tube in a tubeless tire to select the next speed range up than spec so that would support running V rated tires instead of H. ( V sustained speeds 149+ mph, H sustained 130 mph )Does it make a difference in safety, not likely. My R100 is breathing hard at 110 mph and all done at about 115 and I rarely do that so I am comfortable ignoring the need to upgrade the speed rating.
I ran Spitfire S11's for 30,000 miles, getting about 10,000 miles out of a rear and replacing them as a set though the front had more life in it. They are a fine choice for an airhead offering long wear with good grip. The center of the front tire has a groove that sometimes hunted on grooved pavement or on paint stripes but the forks and frames of these things are rather noodley to start with so wasn't a problem for me. The rear will wear kind of squared off too but again it wasn't a problem for me. This last go around I wanted to try something different so I choose Bridgestone BT45's. I think I had to get a V rated front in my chosen size of 100/90-19. The rear is 110/90. I like the 45's very much, the bike feels better on the side of the tire and it seems to turn in quicker. Hard to tell though, could just be the new tire feel though I now have 3000 miles on them. Lots of miles to go.