I have to say, I tend to stay with knowns. Being in squiddise (squid paradise) I'm picky about who i'll risk my neck with.
I've got a close knit local group, the track whores as Papapoi so aptly named us (deserter!

). Also pretty much anyone from here that I've ridden with. We are familiar and comfortable and our expectations are clear up front. No douchebagging. I like to stop after a of bit of riding for a few minutes, but dont expect me to stick around if we're stopping every few miles. If you ride with us, you get a location, a time to be there, a few minutes to be late (alot actually, what biker is EVER on time cept Ebbs), and thats it. You dont show, or catch up, youre outta luck.
I dont like jerks, but newbs dont bother me, and I have no problem mentoring someone who genuinely cares about riding but if you're in it to show off or be "cool", you get nuthin from me.