I made one of the Sloppy Joe variations, Smoky Joes. The original recipe calls for tomato puree and ketchup as the sauce, but for Smoky Joes, you replace the ketchup with barbecue sauce. I thought the original might be too tomato-y for my liking so that's why I opted for the BBQ version. It was super easy and I would have probably finished it in 30 minutes if I wasn't also dealing with a cranky, hungry 18-month-old! :) I do agree with what Darby said about the water (it calls for 1/4 cup)...I don't think it's necessary. I think the tomato puree + ketchup or BBQ sauce would make it plenty saucy enough...and if it needs more liquid, you can always add a little water as it simmers.
As for the taste...my husband and I both liked it. However, we already have a yummy Sloppy Joe recipe from the Neelys that we make all the time, and although we liked this one from Cook's Illustrated, it will not replace our other recipe that we love. (found here)