Indyfan- "triple platinum" means that all three electrodes of the Splitfire plug are platinum plated [or tipped]. Older plug styles only have two electrodes so platinum plugs in that style can be either "single" or "double" depending on how many of the electrodes are platinum.
From what I understand, the Bosch +4 seems like a good design. Someone correct me if I'm wrong, but it seems like I remember reading that platinum plugs aren't the best performance plugs. They do, however, last a long time. So, with a platinum center electrode (for longevity) and 4 non-platinum electrodes (for performance), it looks like Bosch may have something good.
There have been reports, however, of poor performance in older (pre '97) engines when using platinum plugs. For those applications, I just use "regular" plugs.
1997 4x4 Expedition
- 4.6L, true dual exhaust w/glass-packs, K&N air filter, SuperChip, airbox mods, Edelbrock shocks, 285/75R16 BFG ATs, Optima "T-Bone" wheels, and Clarion In-dash CD player.
1993 4x2 F150 Reg. Cab LWB
- 5.0L, cat-back dual exhaust w/glass-packs, K&N air filter, Superchip, fresh paint, and Line-X bedliner.