(of course their link doesn't work, so add http:// before the following)
dominatedominion.com/forum/viewtopic.php?f=129&t=757

It is pretty long and I learned a lot by writing it up and experimenting. I'd be interested in hearing feedback from experienced Jayce players, as well as relatively new players if you think its helpful.

I'd welcome critique and argument, though it would be nice if you had actual logic and reasons to go with it. :-)

I think the defensive masteries are way better, giving you movespeed and CDR. I also run CDR blues, because then I can get 33% with ionians, far better than what you have. Not sure about CDR quints.

Movespeed is vital because of your short range. You should go in to engage, then reposition while your W is down until you think it's safe to jump in and clean up.

Opening Prospector's is really non-optional in high level games. I often don't sell it, as Jayce's items are pretty costly, I can end a game with ionians prospectors IE BFS/cloak LW and Ex Calling, and that's a game where I get lots of kills and farm.

Remember Hyper Charge is an auto reset. I often go in with W turned on, and miss out on an auto because of this.

Keep farming. You mentioned being able to farm with shock blast. To the skies + lightning field is similarly effective.

Shock Blast goes the same distance whether you place the gate in your own face or at max range. It hits slightly faster with less distance until the gate.

I practically never opt to engage on ranged kiters, because I'm the squishy carry and cannot afford to be baited into cc or a 2v1.

My end build is either (in order of start of construction - I won't finish Ghostblade until the end):

Ionians, LW, Ex Calling, IE, IE, PD (95% crit) or Mercs, Ghostblade, Ex Calling, LW, IE, Trinity Force (70% crit), depending on how many assassins I expect to jump on and cc me.

I go Q>W>E>R, but I can see Q>W>R>E working. Having more Es is nice, as it's a really nice team movespeed boost and it gives you more shock blasts. Talith advocates Q>E>W>R.

Oh, an advantage I didn't mention of the Prospector's, besides making you significantly less squishy, is letting you start with one health and one mana potion. The mana potion is worth over 200 mana, don't underestimate it.

I like Defensive masteries also. I just feel that the 10% crit and 10% armor pen are too important to pass up. But I used to run Defensive and that is perfectly legit.

I didn't see movespeed as hugely important. His poke allows him to trade at range just fine and gapclosers will be able to attack you before you can hit them no matter what you do. Melee with no gapclosers you can kite pretty easily as well as knockback. You can always step thru your own gate for a MS boost as needed.

Prospectors is fine. Id suggest each person try it both ways and see which they prefer.

Hypercharge. It does attack reset but doesn't do a very good job unlike most melee resetters. By the time he gets off the shot and I hit W, there is a substantial delay and it gives the enemy a chance to run off if they intend on doing so. I actually prefer getting in 3 almost guaranteed hits, rather than 1 hit, then resetter which might let them get away before I get it off.
If you aren't being focused and they are unlikely to move back out of attack range, then yeah...definitely go with the attack reset property to get in that 4th hit. But I usually just go with the 3 hit, then immediate followup with Gapcloser,Knockback for the kill.

Farming - I mentioned to the skies/field too. But that is melee range of course. Hyper charge is great because you can farm from 2k range off while staying right next to your tower and not getting ganked in no-mans-land.

Shock blast goes the same distance regardless of gate, but it doesnt speed up until it hits the gate. So in theory youd want to drop the gate right next to you. But as I mentioned, this doesnt make hardly any difference so I just smartcast the Q/E together. The only exception is when they are very close range.

Vs ranged kiters, if they wont engage...fine. Poke them to death. But when they do move in to 600 range, at least you have an option to engage them without just being picked apart by their better range.

You are more than welcome to add whatever 'optional' components you wish, including hexdrinker,phage/mallet, prospectors, brutalizer. I like all these items. It just depends on how much tankage you have, how things are going, etc.