I am doing both laser and electrolysis (darn grey hairs). It usually takes anywhere from 200 - 400 hours of electrolysis to clear male facial hair. My electrologist (she is certified) is the least expensive one I have heard of, she is awesome and only charges $35 US an hour. She usually zaps about 500 hairs each hour. If you are lucky and find someone who charges a similar rate, your are talking about $7000 - $14000 for facial hair removal. Laser is faster, and probably less expensive, but it is usually advertised as 'permanent hair reduction'. Unless something has changed recently, electrolysis is the only approved method for 'permanent hair removal'.
Laser is only good for dark hair and light skin. If your hair is red, blonde, or grey, it will have little if any effect.
Upper lip is the most painful, for both laser and electrolysis. Work on the most visible areas of the face first -- if you hair covers your sideburns you could consider saving that area for last.
The pain from electrolysis varies quite a bit. Some areas are not too bad, while others (upper lip) feel like you are being jabbed with a hot needle. The pain is sharp but fleeting, usually 2 - 3 seconds for each hair. It feels similar to plucking a hair.
For me laser is significantly more painful, and it takes longer for the pain to fade. It feels more like being shot with a BB gun, and the pain from each laser pulse may take 15 - 20 seconds to fade. Even then you will feel like you have a mild sunburn for an hour or so. I have already had 12 facial laser session, and #13 is scheduled.
I seem to be getting used to the pain from electrolysis. Although when my estradiol dose was bumped up the pain increased, after a few months the pain dropped back down quite a bit. Electrolysis hurts, but laser hurts like hell. I am also having my legs done via laser, and there are some places that take my breath away -- much more painful than upper lip work.
Estrogen has reduced my body hair quite a bit, but the only effect on facial hair was a slight decrease in growth rate.