Strava adding distance

I know that Strava does it’s own calculations (blah, blah, blah), when importing a gps file, but I’m wondering if anyone else is noticing that strava is consistently giving different results than the F5 plus and Garmin Connect are. I’m coming over from a Suunto. Strava always had the exact same results as my Suunto did, but not so with my F5 plus. I always end up with more distance once it’s imported into strava. It’s a little annoying. Yesterday my buddy and I did the same exact 6.2 mile run, (he’s on Suunto). Once up on strava, he had 6.2 and I had 7.0.