well i have the 2011 krypto sesg and it runs perfect , it doesn't vibrate any worse than the other 110 engines that i have owned or ridden and as to the heat , getting stuck in London the other day taking nearly 30 minutes to travel 20 yards, yes it did get hot and even shut itself down on to one cylinder , but again no different than others i have ridden , i just love this bike , and Simon don't compare the two bikes you have because they are two different engines to start with, maybe catch up with you two one of these days and compare bikes .
the only mod i have done to mine , engine wise is fitted Rinehart 4inch slip on mufflers , lovely sound , had my first service done last weekend and the remapped the ecu due to an upgrade from Harley but no noticeable difference to riding the bike