I've been using the Intermatic units. The compact indoor unit we have had a lot of problems with. Seems to overheat or something when kept inside the transformer and then it just goes off earlier than it's supposed to. Weird thing is this is really spotty. I haven't had it happen on any of the systems I've installed where to total wattage of all the fixtures was fairly low (e.g. under 200w) but I've had it happen several times on systems where the total wattage was over 200 watts. So that's what makes me think the issue is related to heat or amperage. Regardless, with a failure rate of about 10%, in my experience, it's totally unreliable. We've had good success using the outdoor Intermatic astro timers. But I really prefer to have the timer INSIDE the transformer. Anyone got one they use that you have installed a lot of them with good success?