I installed a 127 in a 94 FLHTCU and have run 9500 miles.  i run amsoil 20-50 with an oil cooler.  i also pull atrailer.  the hottest the oil has ever gotten was about 210.  that was at 95 degrees outside temp.  very happy with motor until lately.  roller cracked and took out the cam, lifters, and oil pump.  still waiting to get it back together.  

I have a 100ci Ultima on my custom w/ over 5000 miles on it now and never had a problem with it and it runs like a champ.