It went well. Aside from the fee that it seems every plumber charges for the visit/estimate, there wasn't a thing to complain about. It helps, of course, that they know the tankless heaters forward and back and, as the other reviewer wrote, are authorized to do the fixes by Bosch. But still, the pro who came out immediately knew what was going on, made the necessary tweaks to the heater, fixed the actual problem, and showed us how to deal with it on our own. The bill was entirely fair, covering the visit and time put in, and their man was friendly and professional. Will definitely call them back in the future for our plumbing needs, whether related to the tankless heater or anything else.