@NeiON the build with a devourer is more of a fun build, not a serious one, thats why i have the 2 different options of Attack Speed and Attack Damage, and the build is in my preference, thanks for the response.

Ok, first of all, I don't think getting devourer is worth it AT ALL, no matter what circumstances, it reguires you to farm heavily before the item gets any proper value compared to warrior.
Also I don't see this itemization working in any normal game where you're not super fed. I could go on but I would just repeat what FalseoGod already said, anyway it's pretty nice guide. Just don't agree with the itemization at all

@FalseoGod, thanks ill edit the guide when i can.

Ok, on a quick glance:

1) You rush too much AD. Really, junglers aren't known for gathering enough gold EVERY game to buy expensive **** like Trinity Force after already getting other items. Also, Ravenous Hydra is a lot better overall in terms of damage and interaction with Rek's AoE, if you're getting ruined king you're trying to deal more overtime damage than burst, and thus wasting your Q. If you got BotRK for the passive, you should be hitting your knock with the help of chilling smite already.

2) berserker greaves. Like seriously, don't. No. Not on Rek'Sai, not even if you're fed. Either mobility boots if you wanna abuse your global presence and you're doing well, Merc's if you're against a lot of CC/AP Champs/Fed AP Champ. All Bloodthirster shouldn't even be on the cheat sheet IMO.

3) The guide's too short, specially for a jungler guide. Alternative paths, objective control, controlling the enemy jungle, suggesting wards and spots to ward (as a jungler you're really supposed to help warding the enemy jungle/river), how to play if ahead, how to play if behind, junglers you can invade, how to abuse tunnels for taking stuff from the enemy jungler.

Guide also requires more in-depth approach on each of your skills: how to use them (images if possible), tricks, good escape routes, best spots to gank from,... The information is too cramped and displayed almost "randomly", not following a structure so people know what they're looking for.

I don't know if you have Comment to Vote on, but if you don't I recommend you turn it on!