when listening i just skim around...
intros. interesting looking groove patterns...
most record store recluses arent too fond of you bringing in a portable and running your cheap hard wearing needle on their records from my experience though...
if they have a listening station great. other than that, as SEAN mentioned, its all about the "spidey sense"...
a portable might work better at a swapmeet flea market setting, but even then, its just a distraction from the actual digging imo...
while your trying to listen to some record, the digging fiend dude in the rubber gloves and respirator just copped all the heat... then glanced at you over there with your headphones on and snickered to himself....
