The barn conversion is lovely - it looks very nice and is generally very well equipped. There are four bedrooms, allowing 8 to sleep comfortably. Two en-suites and one more bathroom mean that you can visit with a large group and still have a degree of privacy (especially with the layout, which suits two groups of four very well).
There's a nice shared garden, and a smaller garden just for the barn, giving plenty of space. There's parking for 2-3 cars, but there's quite a steep slope out, and after the rain, one of the cars in our group struggled to get up it.
The baby-grand piano was great (but could do with tuning!), and our musical prowess was put to the test!
A few reviewers have mentioned the flies - yes, there are quite a few, even this late in the year - I can understand it wouldn't be too nice in the summer. The owners do all they can, and you are in the countryside, but (having spent a lot of time in the countryside), there are more than usual.
The other minor niggles are that the wifi is terrible - it does work, but drops off frequently, and is really slow - this may not be the owners fault, or it may be that they need to upgrade packages - however, you should be enjoying the countryside not using Facebook!
The only annoying one was the number of passive aggressive signs around (e.g. 'we love dogs and fake tan, but please please please do not get them on our bedding or furniture else we will charge you as we've asked you nicely' (if you don't want dogs on your furniture and bedding, don't allow dogs!). Also, it's a bit unusual to be told to empty the bins, particularly when the bins are at the end of a long driveway.
Overall though, this is a nice place, and we'd recommend it.