LoadMaster here, never posessed any of the Dillon or RCBS stuff, but my friends swore by them. (Hey, I had to be different)
I chose the Lee product because I found the press to be solid, and for $215 I was able to have a complete press, set of dies, brass feeder and auto primer and carbide dies for .45 ACP ready to go. With carbide die sets running less than $25, I saw a nice, quality and economical solution for my reloading needs.
Been using it for quite a while now and have run into zero mechanical issues. All of my reloads chamber and fire just fine, no issues with primer installation or mis-sets, haven't crushed any plated rounds due to poor case sizing or crimp operations. I may change my song in a few years, but so far the LoadMaster has been better than I expected based on my opinionated Dillon-ites friends!