I like starting the takeoff roll without flaps and then selecting 10° during the run. This reduces drag and gets you to speed faster.
10 degrees of flap will cause so little extra drag at the low speeds you are doing at the start of a takeoff run that doing this will make no noticeable difference whatsoever. I'd think that all it does it cause extra distraction on the takeoff run, and give you the risk of going through the hedge if you set them wrong or they don't operate.