I'm using 2 PT04 receiver + and 1 transmitter for many months, probably close to 9 months I think.
I've changed the CR2 3V batteries in the receivers and also the 23AE 12V in the transmitter, and they are working fine - except that they are physically fragile - they won't survive too many topples... and sure enough, one of the swivels broke off when my light stand toppled, along with the Umbrella/flash holder...
Electrically, my set is working fine. But I do know that these things are mostly hit or miss and they aren't built to last, like my given replacement cycle for these things are as short as 4 to 6 months max, and I'm amazed that they could survive till now, though physically broken, they are still running. They do fail to fire or sync properly when you're at some particular locations - where the surround structures may serve to function like faraday cages and channel your radio signals away or severely weaken them.
Anyways, I've changed the system to a new one that integrates the Umbrella / Flash holder with the Receiver, and it runs on AAA batteries at the receiver, and uses the 23AE in the transmitter. (transmitters need high voltage) which goes for $65 a pop
I compare that to the system I'm using, it's actually cheaper by $15 a set
PT04 T/R set = $45
Umbrella / Flash holder for light stand = $35 (GT=$80)
Of these, there are models that fit directly onto the ball head of a tripod, this allows you to position lights at very unique positions, very low or very high, or very uneven surfaces, which I consider them to be a boon when doing location shooting, or even hang them around, like what you can do with a gorilla pod, and at the same time, attach a umbrella.
I bought 3 sets of those - anyways - the disadvantage is that there's only 1 channel :sweat: anyways, there's no interference incidents so far, and the usage of AAA batteries simplifies logistics and I can use rechargeables...