thought i would provide some feedback on the performance of the cooler.
After brewing I placed a fermenter of koelsch(using 1007 german ale yeast) in the cooler on 19 December at 15c. Used 4 x 1.25l forzen bottles around the side, and the fermenter has a small two piece air lock(the large one or s bend airlock would not fit).
Closed up the cooler and initially the temp dropped to 10. Took the fermenter out to warm to 16, the yeast then kicked in, chucked it back in the cooler with the ice bottles.
Temp has remained at 15-16c whilst ferment is active, changed bottles morning and night. The fermenter has been inside where the ambient temp has been around 25.
Conclusion - great cooler for maintaining temps in the mid teens - so perfect for ales, koelsch, wheats etc
Intend using it next as a portable cooler for my 3 gall keg for takeways