I've only give the Isn't Anything remaster a cusory listen, but the sound quality has definitely been improved. It sounds clearer. It's not night and day different, or course, basically as with any remaster how much you like and listen to the original should determine whether you should but it.
Actually, this article is so bad it almost unreadable. Not only is this person useless at evaluating music, his writing is absolutely awful, too.
'Coarse anthemics'? Has this Robert Leedham person ever even heard Slowdive? What a cloth-eared idiot...