No need to worry about whether Strava or whaoo records more accurate distance. When you upload the fisnished ride to Strava, you can run a distance correction function in Strava, which will correct recorded distance for errors according to Strava data. I find distance difference between what the wahoo records and what Strava thinks is usually marginal, a couple of 10ths of a mile at most. You can do the same correction for elevation, and I find Strava elevation more accurate.