>>>Does anybody have any feedback on Skyline Aviation?<<<
You must have some doubts or you wouldn't be asking this question after your visit for a trial lesson.
I recently moved to the area and attempted to fly from L.Gransden which involved joining Skyline.
My experience was "Bad", they were very clique-ish and wary of strangers... I like to think of myself as an open person but they certainly did not return the compliment... as a result I will not now ever go near the place again.
My neighbour regularly flies from Bourn and Conington and rates them both.
Me? I'm scouting around for a share in a Jodel/Cub in a quiet field somewhere far away from L.G.