Replying to Size skis

hey, i think im probly going to get scratch fs skis now as my first pair- not many people are ripping them and they seem pretty forgiving for a novice but still quite stiff for all mountain. Would of liked some PE's but seem a bit hard to obtain here in the UK. 1080s are getting a bit too much flak and TMs seem to have durability issues! obviously id love to demo them but the only skis available for that are 1080s (poorly rated) and PE's (sold out).

So i need to decide which size to buy them in, not sure what sizes they come in but im 5'11-6' and about 70kg (11 stone) and pretty new... ive only seen some 168 but im guessing that is too small and that i should be looking for 17*?

any help would be great, thanks