Tempo... You had better a lot of reading about KAL and RAL.
I looked into it once (a few years ago) and the end result was NO WAY! As a Capt at KAL it wasn't good and as FO I think you could be in for a VERY VERY tough time. Lots of horror stories out there. No need for me to repeat them as I can't speak from first hand experience.
Now add to that the WORST recruitment agency in the world (from my direct experience) and it just gets harder. Your contract with that scum RAL is not worth the paper it is written on. Again, do some key word searches.
Good luck with your decision. Just go in eyes fully open, that's all.