I will add the Jayce matchup shortly. Usually you can just go Doran's Shield early and build as you normally would. If you can't dodge Shock Blast then go for a Seeker's Armguard.

"Do you even lift?" became "Do you even rift?" which sounds like Kass is getting youtube.com/watch?v=0_C2HJvtRDY Syndrome.

Any opinions on how to play against mid jayce? Or could you add him?

Thanks for the feedback. You don't level Q if you know you're going to be team fighting a lot early. That's why it's titled "Lane Matchups." The skill order you mentioned is even in my guide, listing both Q first and E first, complete with pros and cons of each.

Tear is extremely useful all game, for only 700g. You're just not going to get anything better for that gold. But if you know you're going to have access to blues or the game isn't going to go late (a risky gamble in my opinion) then you can skip it. That's even mentioned in the guide too. =D

Didn't like the guide for several reasons. Enjoyed the in-depth of it, but really, I don't like:
1.How you say most match-ups should be leveling Q first. In higher level of play, maxing Q isn't enough poke damage for today's mid champs and puts you in a risky spot, and most champs mid will realize your maxing Q first and easily push lane to assure you miss CS under turret while they roam. A previous guide I read stated that 2 points in Q is enough for laning phase and to max E first, which I have done with success and cleared waves easily, and proceeded to roaming. Not roaming with Kassadin is a huge waste to his potential.
2. Grabbing a tears. Tears at most adds 1k Mana after about ~20 Minutes when kassadin is a strong mid game champ. You lose laning presence and its not all that helpful to survivability tell late game, but even then, buying a mid-late game chalice/unholy grail will more than make up for the mana issues, assuming you aren't spamming your R off the Wazoo, coupled with a rod of ages. And the damage it gives you is pretty good(Seraphs Embrace) but Kassadins Base Damage is strong on its own and you probably will only ever need is a rod, HG, and VS/RDC for damage. And HG is more of an on demend item now a days, allowing you to reach your low cooldowns faster without having to deal with enemy retaliation. Should be more of a priority to get, even if fighting an AD or not.

I do like:
1. Your lane match ups, and how the detailed you go into them.
2. Riftwalk expanations and tricks.

But I still dislike the lack of synergy as a whole for your skill and item set up.

Tear is a really strange item. The moment you buy it, you're practically wasting 700g, but it gets better and better as time goes on, eventually evolving into the god-like Seraph's Embrace.

Sometimes you can't afford to drop 700g that early, like when you're getting stomped in lane by just a little bit and a Blasting Wand would swing the lane in your favor. If you're already winning the lane (and 700g won't hurt that) OR losing so hard that a Blasting Wand won't swing the lane in your favor, then I would say go for Tear.

tl;dr Tear decreases your laning presence but increases your roaming & late-game teamfight presence.

Coming from someone else you mains kass (with the deep one skin!!) This guide is perfect. My only question is after what item to you build the tear? This is the only item i do not use and after using it on aram it is godlike, but i really dont see the need for it otherwise, is it worth delaying a roa?

Glad I could help! And I've had a lot of people ask that, I guess I should get around to it some time. I just don't know specifically what to do.

Thumbs up Bro (Y)
Such a detailed guide..

Maybe this is too much asking, but could you pls do an ingame commentary?

Hey Rathalos, check my guide and tell me what you believe about the items and ROAMing.
http://www.solomid.net/guides.php?g=53357&c=2032601367123428