Well I think the shoes depend on the champions you have to fight against. When you have a slower hero like Cho'gath you don't need such speed because he can't run away anyway. But a fast hero like Kayle is difficult to get so I guess boots of swiftness would be got for her. And you have to think about Skarners Q and W. The Q slows the other one by 45%, and the W gives you a 23% bonus speed, so this is already like boots of swiftness.

@ZealotRush, the reason why I didn't take life steal is because of his E. If you are focused in a team fight you will die anyway really fast, even with an hextech gunblade, and outside ob battles you can just heal yourself up on minions and neutral monsters.
And about your guide: I've never played Trundle before, so I can't give you an opionion, I'm sorry. : /

AP skarner ftw! I love the build! i wouldnt get sorcerors shoes thought because in my opinion boots of swiftness give skarner a huge utility boost. but crystal sceptor and nashors tooth =YES! I am supprised however that you dont have any spellvamp will of the ancients and hextech work great for ap skarn. but overall a great build!

if ya have some free time i would love a review of my trundle build too :D

I see your reason behind the Sorc's shoes, but i find the boots of swiftness to be a tad better, because your ult only lasts 1.5 sec with the swift boots you can drag your target further, closer to your teammates as well as catch up to someone so slow them with your Crystal Slash, especially being you need to drop it on them 2x for the slow to affect them.

Alright thx, it's my first guide so I'm not that experienced ^^

Good guide so far, keep up the good work. But you should set it to require comments to vote to avoid trolls. +1