I have flown the 6100's in almost every Parkzone plane I have had, as well as several of the HP F-16's.
I have flown them out to around 1/2 to 3/4 mile away in a Radian and never had an issue. (Radian gets too small for my old eyes to see clearly! LOL!!)
I ALWAYS use a separate UBEC with them though, the exception being my Pop Wings as there are only two servos and an ESC.