You may well be right that the Dunlops are better than the Bridgetones but regardless, the 20s and their W-rated 275/40 and 315/35 tyres aren't what you want on rough, poor-quality roads, more so if the road is unsealed. This is not so much a criticism of the M50d's tyre and wheel package but more a comment on what's best in my neck of the woods - out in the boonies!