Considering a first e-Bike purchase. Thinking of one with a rear hub motor but having the battery mid-ships somewhere to improve weight distribution. Quite a few bikes have battery semi-integrated into the downtube (eg. Juicy Roller, Kudos Sprint and Stealth). How secure are these from theft? Is it still advisable to remove the battery when leaving the bike locked up for any length of time? Came across the Westhill Classic where the battery inserts wholly into the bottom of the downtube, but not the largest capacity.