I have worked through the design issues with the Mann Lake Feeder 1)screens not big enough and the bees get from hive to tray; 2) plugging all ventilation holes above so outside bees can't get in - I use an inner cover and prop it open with 1/16" cardboard and outer cover. I haven't had 'major' issues with the comb on the bottom of the plastic tray, only in the center divider. Other than that, I do like the feeders as I don't disturb the bees feeding the first year packages.
In reading about winter feeding, it seems I may have an issue with cold syrup. I can certainly warm the syrup, and put on only what they can take in 24 hours. Has anyone played with putting a solar cover (extra double glazed window) on top of the feeder and letting it warm for a few days? I may have to play with this with a cheap recording digital high/low thermometer.
Caveat: I only have four hives, 100' from the house. It's not a major effort to check on them.