I have also magnesium firestarter (but I donīt use it at all, I have casted it aside). But there was a warning that you should not shave the magnesium in advance and carry it like that. I guess the warning is there for a reason but I donīt know what exactly would be the problem.

As for the Spark-lite I donīt trust it at all - but thatīs just my experience and personal opinion. Anyway you have a backup. See my review on EDC forums http://edcforums.com/index.php?topic=17216.0 (my nickname there is "vfx", "raptor" had been already taken).

I would also add some small candle to your kit.