James, having swopped to Iridium in the last few years on various cars I won't go back to normal spec
I swopped out some Iridium a couple of years ago at 40k plus miles, absolutely no erosion, & gap was still to OE spec
If I can get them I prefer NGK, with Bosch as second choice
Don't forget, if you 'extend' or ignore plug swops & the gap gets too wide you can bu66er up your coil packs
