I switched from Dunlop to Avon. That center groove on the Dunlop liked to follow tar snakes and tarmac seams, and made crossing drawbridges (we have a lot of them down here) a real adventure - the tire would jump from grate to grate as the groove caught on the rib of the grate.
The Roadriders, with their modern tread pattern, don't have that issue.
'73 Norton 850 Commando - 3030xx
'69 Norton Ranger 750 - P11/1289xx
'67 Matchless G15CS - G15CS/1235xx
'61 Matchless G80CS - 61/G80CS/41xx