I usually get mine at Kohl's, 600TC or higher as well and I always feel the sheets because some just don't feel right, though I do have one set from Target that I haven't yet used.
Also, I have flannel sheets from Kmart - the Martha Stewart ones. Recommended to me by LOTS of people as they don't pill like normal flannel sheets do. I know it's summer and you don't need that yet, but later!