andre;
I run Bosch platinums in ALL my stuff. I've found that,on average,they've given me about 2 more miles per gallon over AC plugs,and the damned things seem to last forever. Well worth their cost!
This is just MY observation-I'm sure someone will have proof to the contrary...
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