Hi,
I personally recommend SanDisk or the NOOBS SD card (which is Samsung branded). They provide a good combination of performance and reliability. SanDisk cards certainly have ‘quirks’ as do most cards, but upstream kernel commits shows that these are dealt with quickly, and SanDisk cards are widespread enough that they are treated well.
Samsung cards provide very good performance, but @DBMandrake had to send one to the Raspberry Pi foundation recently as it was not working reliably under the SDHost driver. They are a bit more expensive than other cards, and while they boast faster speeds, you may not notice this with regular OSMC use.
And of course, we sell our own SD cards at the OSMC Store. They all come with a lifetime warranty and come preloaded with the latest version of OSMC, so you shouldn’t have any trouble with these cards and OSMC.
Sam