Modern custom plugs are superb. An old set I had used to get quite uncomfortable after a day or two's (on tour, big kms per day) riding but my new ones are fantastic and I don't bother me at all - I can sleep with them in no problem. It's only around town that I do not wear them.
I have in helmet speakers and can still hear my music with the plugs in. I also have a set with ear buds molded into them but unfortunately I find it very hard to get my helmet on with them in so don't use them. I am considering pulling the buds apart to see if I can make everything a bit smaller.
I'd wear them just for the hearing protection but as a lot of guys have said, they most definitely leave you fresher after a days riding than if you weren't wearing them.
'08 Vee: Suzy luggage, Crash bars, Rad Guard & front mudguard extension, Zumo 550, Oxford Hot grips, Stebel, PC-8, 12v acc, Scott oiler & lube-tube, Remus Revolution Cans, Bark Busters, Phillips Extreme vision +100 bulbs.
'08 Concours 14: Rad guard, Stebel, Oxford Hot grips, Projekt D Screen, Hugger, GPS mount, helmet locks & front guard extension, Zumo 550, Stebel, Phil's rack & Givi V46, Sheepskin seat cover, Phillips Extreme vision +100 bulbs.