I like just plain ol' Bosch Platinums.I started using them in a car I used to have that would oil-foul the hottest AC plug I could get after about 2 days of use. With the bosch plugs,I could run a little over a week before it'd oil out that plug. Then I put 'em in my 80" Harley,and gained a couple of mpg,plus it started easier. Now I run 'em in ALL my vehicles (except the dirt bike-I havent been able to come up with a match for that one.)
Speed

1954 GMC 350
1957 GMC 1/2 ton
1962 Chevy C-30
1952 Chevy 6400 dump bed project truck
'98 Harley FLSTC
'66 Pontiac Catalina
'76 Chevy 1 ton Duallie
'84 Bronco II
'78 Dodge W-200
'81 Toyota 4X4 truck