Cheers all, unfortunately I should have paid more attention at the meets and had a listen, now I have to make a rushed decision. The old Micron can I had was a lovely deep base, even the dealers commented on it sounding lovely. As to performance diff, with the original can on it had no power at 5Krpm, which is 70-80, just where ya want it for motorway. Ended up having to keep dropping a couple of cogs to overtake, with the Micron, not a prob, just left it in top gear,
.