Interesting indeed. Out of 2 Royal kits (4/2010) 3 batteries have developed problems, one was terminal and replaced by the vendor without complaint.
#1 overheated and was caught and yanked free after 15 mins of being plugged into the standard USB we've used for eGos for months without problems. After explaining to the vendor it was determined as defective and replaced.
#2 began continuous button/light flashing, discovered the USB connector was loose, and moving the USB cable made it do weird things. It still charges when we get the cable wiggled just right, and holds an average charge, but I don't trust it so it landed in the parts pile.
#3 developed button problems with sticking and firing whenever it wants, it too landed in the parts pile as unsafe. Yes I tried everything to clean it, thinking it was juiced or something, but to no avail.
2 atomizers also died within a month of moderate use, but that's another thread.
They seem chintzy for the same money of the eGo (eGo PT kit $34 vs Leo PT Royal kit $37) and I've never had a single problem with our eGos. The simulated marble coating on one battery is flaking and chipping, and the logo paint is gone after a mere month of use. Not the quality I was hoping for, and with the new eGo DC LV 4ml cartos out now it looks like I'll be going back to the sturdy dependable eGo.
I'll try one Leo Pro but if it has any issues the Leos will fall by the wayside for us, the bang for the buck just isn't there IMHO. We can't afford $17 for battery and $20 for 2 atomizers every month, that's insane.