I have been following a discussion on alternatives for the OEM NC coil packs on m.net. https://forum.miata.net/vb/showthread.php?t=637421
People running FI starts to see problems ~ 300whp with spark blowout and knock/misfires.
I found this video on a very thorough test on 16 popular coils that are commonly used for upgrading from OEM. It's unlikely that I will ever run out of coil on my setup, but if I do I'll def go for the R35 coils.
The quality of the Motive Videos on youtube involving PRP are very good. I have not a lot of interest in 2JZ or RBxx blocks but their videos on testing hardness and cylinder wall thickness and weight of different blocks are fascinating.
I wish we saw this dedication and product support for the NC.