In my experience, either get the cheap Autolite plugs and replace them every 30K miles, or spend more and get the
NGK IX plugs that actually do last 100K miles. Bosch Platinum actually use Yttrium for the electrode, and while they are better than other platinum plugs, they don't last long enough to make up for the extra cost. Two brands I would avoid are Champion and Denso.
It's probably obvious, but I'll mention it anyway, use Anti-Seize on the threads.