I have not, but I am looking at the same loaders myself...
All I would say is this: Tigercat owners swear by them...very very loyal.
Timber-King....haven't heard of owners praising them like that.
But...whichever machine has the best service after the sale...that's the one I'd buy. If it pukes a turn table bearing 20 days after it's dropped off....which dealer will help you out?
lol id say niether one cause they are from a company called dutchman global. Ive ran a tigercat before, and it was an awesome machine. everybody says the tk560 a prentice 384 with a cat motor and a yellow paint job