It helps insurance most
An Ace sidecount can increase the insurance efficiency of High-Low quite a bit You end up treating the Ace like a low card for insurance purposes, forgot all the details. Probably worthwhile if you want to use High-Low and if the sidecount doesn't distract you from doing anything else.
On the other hand, if you are experienced enough to effectively use a sidecount, you're experienced enough to use a stronger count than High-Low and your effort might best be expended there.