I like NGK DR9EIX plugs. They're Iridium tipped and have a much smaller center electrode (0.4mm vs. 1 mm) than a regular plug.
Iridium is virtually impervious to acids and it's acids that cause corrosion at the center electrode. Burning a sulphur based fuel (gasoline) creates small amounts of sulphuric acid and the center electrode is affected, rounding off a bit over the miles. Platinum is quite a bit better than the standard materials, but Iridium is a lot better.
I just had the plugs out of my 2003 Bandit 1200 today when I did a valve adjustment. These plugs have about 13,000 miles on them and the center electrodes are still sharp and squared off, not rounded at all. The gap hasn't changed in those miles and with a little anti-seize they went back to work.
While expensive at about $10 each, they're very long lasting and based on my experience they'll probably go another 20 - 25 K miles before needing replacement. The body appears to be plated -- no corrosion was noted during removal and replacement, and they came out easily.
Iridium tipped plugs are available from NGK and Nippon-Denso. The N-D number is IX27. Both NGK and N-D cross reference these numbers to the J9B plugs recommended by Suzuki. They're both available in the Dennis Kirk catalog <
www.denniskirk.com> and can probably be ordered from any dealer as DK is related to Parts Unlimited.