The Laing Autocirc has an appliance style timer built in so you can choose numerous windows when the unit can operate by its thermal control and windows when it will not operate.

A solid unit... have had mine for a long time and just let it run 24/7 using it's thermal control and have never seen an increase in my electric bill.

I would think that most circulators can be run by a switch; you just plug them into a switched outlet and wire it to a switch that is convenient for you.

You can take this one step further and wire up an off-delay module and a motion sensor to turn the circulator on/off automatically when you walk into the room.

I used a Tyco VTM2 Off-Delay Timing Module with a ~210 kOhm resistor (to set a 15 minute off-delay) and an IR motion sensor. When triggered, the motion sensor either opens or closes a set of contacts on the relay, which closes a line voltage circuit and starts a timer. The timer gets reset anytime there is motion detected. When the timer expires, the live voltage circuit opens. The line voltage feeds the hot side of the outlet that the circulator is plugged in to.

Redytemp circulators will do what you want and if you want to use your own pump their TLC-X1 controller can be purchased by itself. Just plug your pumps powercord into the controllers power socket and now you have all the control you want, on-demand operation, timed, motion sensored, etc. I like that it can be activated from anywhere in the home with the right options. The chilipeppers are noisey burnout alot, while the laing circulators state in small print that your required to periodically inspect and clean buildup from inside the pump. Whats the time interval for periodically anyway?

Here is a link that might be useful: Hot Water Circulation Control with Redytemp TLC-X1 controller

Routine maintenance, what an inconvenience! Takes all of three minutes for me to remove the pump and disassemble to inspect and requires NO tools.

I've owned my Laing Autocirc for over 5+ years and have checked the buildup in the pump for the first 3 years... never found any.
I have very hard water and a softener that provides ZERO hardness water so YMMV.

I'm always amused when people dismiss something they never tried or because of anecdotal information, but don't listen to those who have had have one... for a long time.