I have 3 products from RH Designs:
Stop Clock Vario timer
Flasher
Process Timer II
All are excellent and well thought out. They do take a bit of "getting used to" but once you get some practice they become second nature and a natural part of your workflow.
I don't have the power supply for the process timer and have not had any problem with battery life. My only complaint about the products is the somewhat niggly process of getting the appropriate power supply but I think the source of the problem is government regulation which is not surprising.
My other complaint about the Process Timer II is the display. It should show the measured temperature at least to verify that the thermometer is working and to allow comparison to my existing thermometer. Even so, I consider the timer indispensible. I calibrated my processes at 68 degrees to suit the timer and now I try to get the temp close and let the timer adjust. No problems. Also, I think it could be larger to allow more buttons for simpler use and a larger display for the temperature. Oddly, when the time is above 10 minutes, it shows the seconds only in increments of 10. Once the time has counted down below 10 minutes, it shows 2 digits of seconds, e.g. "59" instead of just "5." I have gotten used to this and it is no real problem, but I would pay for the extra digit and temp read out.
Buying in Great Britain and shipping to the US has been no problem. I receive their products more quickly than I receive packages from Oregon. Their communication, when needed, is excellent.
Also, there are no current competitors. I have a Gralab 900, a Jobo process timer 8, used to have a Jobo Multitronic, etc and none are better. I have never used the Zone VI compensating timer but those fetch a substantial premium used.
If you buy just one item from RH Designs, buy one of the enlarging timers. Or for less money, buy an F-Stop timer from Darkroom Automations and the process timer from RH Designs. I think these are indispensible products for a modern B&W darkroom.