I particularly like to review indie works. Sometimes I don't bother with trade published authors though.
I will review 0 - 5 stars for an indie writer and although I'll feel bad giving less stars, I'll still do it if I feel I need to.
Recently I struggled to review an indie author whose book seemed to be quite popular and although I loved the story, I found the writing really needed a few more editing passes. I gave it 3 stars for the excellent story, but on the writing alone I would have given it 2. I really thought it was a 4-5 star story waiting to happen though so the 3 star review was a disappointing one for me.
It's definitely a balancing act though. I have a great deal of admiration for authors in general and a particular soft spot for indie authors. I like to think that my review of an indie author is helpful to them either way even if my review doesn't earn them many stars.
I've been planning to set up Wordpress so that I can start an indie review site actually but I'm struggling to get the thing to work.
EDIT: Wordpress suddenly installed properly for me and worked. So back to work for me.