Pros
Great at laning, intese staying power early game.
Rabid Bite hits like a truck early game.
Fast, and great survivability.
Can chase like no other, many slows to catch up to even a frisky Yi.

Cons
Squishy, to a point.
Susceptible to stun/nukes.
Sometimes your too awesome.

Trundle is a very, very underrated laner. I just made this homebrew recently, and had such success I decided to make this build for all to try out and see. The fact that Trundle steals AD/and other things, turns him into a Yi/Trynd/Xin killer. One weakness seems to be nukes with stuns such as Annie, and Ryze, so play carefully when Tibbers is out and about.

This is just a generic build I use for a Physical Carry, its straight forward, and to me, the best it can be, open to suggestions.

These are just my personal favorites, they are obviously open to debate, use what works best for you.

These are just my preferences to ensure kills so that I get fed, there are obviously other options if your in 5s, such as Teleport for map responsiveness, and ignite would be a viable option aswell.

Trundle CAN be a bit of a faceroller, but generally, you want to drop Contaminate, and go to town with Rabid Bite, and your Ult, focusing an AD champion.

Play aggressively, your lifesteal late game will allow you to tank practically a whole 3s team, and double/triple kills are not far out of reach. Use Exaust wisely, paired with your other slows like Pillar of Filth and Contaminate to ensure kills. You will get fed easily, and SMASH any AD opposition. Last hit as much as possible, obviously, play smart. Abuse jungle buffs/dragon when you don't need to be in lane.