I just converted my pool a couple of weeks ago and from what I've read on here, even though it says the concentration is that high many times it isn't especially if it has been on the shelf for a while.
In my area, K-Mart had there brand of bleach on sale for $1 for a 3 quart bottle and also the Kroger in my area has 4 3quart on sale for $5.00 (both 6 %).
It took much more bleach than I thought it would, but it has really been worth it. By the way, I think it was late in day 2 or early in day 3 or my conversion when I really started to question what I was doing....but I promise it is worth it and it is worth all the trips to the store for bleach.
Also, if you have an above ground pool, remove your steps at some point, when I pulled mine out I had a lot of baqa goo underneath them.
Good Luck and you will be so glad that you did this!!!