Labs are, to say the least, fun. My yellow lab is about 5, still has his berries, and is horny as a boat load of bastids. He's gotten out to go after the neighbors goats (I swear I am not lying), and the other neighbors bitch (the dog

). Once, I had just driven back from Ocean City, and was dog tired, and he got out for a nice run. Oh, the hills were alive with curses of all kinds. My neighbor got him, and said, jokingly, I could've gotten him without all of the cursing, which embarassed me to no end when the adrenaline wore off and I realized what I had said.
Labradors will bolt when they hear thunder. We can't hear it, but they can, long before storm clouds even show up on the horizon. My family had a lab mix that ate our back door trying to get in, and ate our back gate trying to get out over the years. He got one of our golden retrievers scared of storms, and they both got out, ending up with the golden getting hit by a car. That same yellow lab got another of our goldens scared of storms too. We're planning on getting a yellow lab puppy, our current lab is not afraid of storms, just real close thunder claps, so the forecast looks good.
As far as em getting tagged with a microchip, it's a great idea, but the farmers up here, hell even the yuppies, would probably shoot first.