I stayed at Wallslough the last week of March 2013 with a large group of friends. It was unseasonably cold in Ireland at this time and can relate to what others have said about the heat. We spoke with the caretakers and they advised all of us how to modify the heat in all the cottages so we had plenty of hot water and heat throughout our stay.
Our group rented out all 8 cottages and while we didn't love having to call a taxi every time we went into Kilkenny, we know well enough to get your taxi drivers name the first trip, negotiate a flat rate and then tell him you'll call him directly all week. Between our group, we had 4 different drivers that would give us the flat rate which was more than 30% less than the metered rate.
I do wish there were better instructions for the washing machine however. The type they have is not common in the US and most of us were guessing at how to operate it. : ) But, the fact that they have them at all is fantastic. Also, the refrigerators are just the large dorm fridges, very small, so plan to shop a couple of times during your stay.
My one complaint is about the wifi. It's seriously nonexistent. We only had it in Cottage 6 and even there, it was spotty/weak. In this day and age, I feel like wifi is a must, in every cottage, and a good, strong signal too. I had work that I need to stay on top of (even during my holiday, sad, I know) and the wifi issues made it very tricky.
Do NOT leave any food outside as there are stray dogs that pass through. Small, adorable stray dogs... but they will steal your bread. : )
Lastly, make sure you buy plenty of peat for your fireplace. We almost constantly had a fire in the cottage we used as the Gathering Space and went through it quickly.
Overall, beautiful place, clean and just generally lovely. Would definitely recommend and stay again.
p.s. vacuum pack and bring your own pillow. no one in our group liked the pillows. too flat. : )