if you are trying to mig weld;
you should try to push the puddle
-better looking weld is the main reason,
-most people push for sheetmetal,pull for plate steel
-it is easier to control,
-see your work while welding is better in my opinion
and if you ever go and try to get a mig welding job
and you pull the puddle, well you won't get the job
unless it is flux core wire
decent article below
http://www.customrodder.com/tech/060...ger/index.html