Honestly you are better off just shooting them at the local matches if your looking to improve your classification rating. I have not seen anyone do 6 good ones in a row. But they are good for getting a quick classification if you need one.
I’d really like to see classifier matches more often. I get to matches when I can but I work a lot of weekends. In the past 14 months I have shot 6 matches and only 2 of them even had classifiers. It makes it hard to move up when that happens.