Using the right tools for the job will pay for itself in time saved and less of a change of injury. Last week after working on a friends bike I ordered a PW4 professional pedal spanner from Park Tools. The week before while repairing a friends bike I bent the jaws of a 15mm snap-on spanner. The pedals were jammed onto his bike that is for sure.
The funny thing happened on Wednesday. I sent Bam, (seen here in an older post after coming off his MTB) a mate I have not been able to catch up with recently an email asking how life was traveling. He sent back two photo of his finger after trying to get the pedals of his mountain bike. That afternoon I got home and the PW4 was in the mail box.
Moral of the story is use the right tools for the job.