I bought an IQUE110 after I got my 18.5 WSM and had some problems keeping things on an even keel. Now I have a 22.5 WSM and I only use the controller for extended overnight cooks. Works like a charm most of the time. Don't bother with anything on my big offset. It takes too much minding and refueling to leave it alone for more than an hour, anyway. The WSM pretty much stays where it lands, usually around 275 which is pretty much what I want, anyway. With the IQUE I can set it at 225 up to 300.
BBQ Apprentice - Old Country Brazos offset, 22.5 WSM, Various gassers, portable grills, etc.