A friend of mine is using 5 gal. polypropylene to ferment test batches. I told him he'd be better off with stainless or even glass, as I think plastic will leave a nasty taste as it's too permeable. Am I wrong? I've always thought plastic to be a bad idea.
As long as the bucket is food safe and fermentation/conditioning will be less than a month, then there is no problem. Just be careful cleaning because scratches will harbor bacteria. All of the lower cost beginners homebrew kits come with plastic fermenters and bottling bucket.
Food grade buckets are ok, although personally I don't like using them either. As wild said, scratches create areas for bacteria to thrive. I didn't know there was a time limit of a month on them though; why is that?