Michelin Tires

Hey all, I hope I did right today. I ordered some new Michelin tires for my bike. I had read that their tires are sized smaller than the number indicators? I ordered the M-12 130/80/18 and front of 90/90/21. Are these going to be the same as say, Dunlop 110/100/18 and 80/100/21? I have tubes for the 110/100 and 80/100 will they still work too?
Thanks
Lew

Smit-Dog;
Thanks for the link. I don't know how I missed it in my search. I read tons of posts recommending Michelins, but somehow missed that one. Anyway, thanks again, I have all the answers I need.
Lew