I used massive electrode spark plugs in my Husky for several years
(about 1500 hour flight time). They worked but needed to be cleaned. I
switched to fine wires about a year ago (300 hours), and have not had
to clean them. They are also supposed to last practically forever. We
shall see. When you do clean them use caution as the sandblaster can
damage them. Also, if you drop one, and break it, it is more. I run a
Seaplane, where NOT starting can be a major event (and need hot start
reliability). They are supposed to be better for that as well. So far
so good, no complaints.