We have so far been avoiding the "fondant-with-a-bit-of-protein" types and just using the high protein ones. We find that we can very accurately correlate the brood areas with where the bees are eating the patties. This seems to indicate that they are using it. In fact it is a very good non-invasive way to estimate the size of the brood nest.
Our bees seem to do well on this system. We don't get any winter losses, except for the odd late supercedure. We averaged 135lbs per colony this year (plus leaving them enough for themselves, on nationals, just "local" bees) despite having a dreadful drought with everything stopping flowering - which meant lack of pollen as well as nectar late summer. That's why some of them are a bit low on pollen, I think. Even the ivy is a bit disappointing this year and we are not in a heather or balsam area either.
We think giving them patties is an "insurance" that allows the bees extra leeway to build up winter bees in better condition, if they need a bit extra, if you like.
