Can you use cheap blades, yes. But as Rodney stated, you never know what you are going to get. I have a helicopter at my house right now that has fiberglass blades on it (600 Nitro, working on it for a member here) and they came to him with chips in BOTH blades! Right at the trailing edge tip. Missing all of the paint and gel coat. I told him that they could delaminate in the air and they definitely could.
As for replying, the articles and the forum threads are linked. When you make a reply in the article section, it is put into the forum thread as well. This was done this way so that when an article was made, it was made public on the forum as well with a link to the actual article. So no worries on where you reply, I will get it.
Read my other post on some tips. It's a little more money, but it's far less than crashing this 600 again.