In my experience, wasps hurt more when it happens, but there venom doesn't seem to have as much effect on me as yellow jackets.
I was going up a ladder between roof levels at work years ago. Just as I put my hands on the loop rails at the top I got hit by wasps in both wrists. Holy F'K did that hurt. Was all I could do to take the last step up and then run across the roof to get away. Hit my Nextel and told the boss to get someone up there with a couple cans of spray ASAP so I could come back down!. An hour later it just itched.
Another time got nailed by 6 yellow jackets while mowing. Didn't hurt near as bad when it happened. Hour later I went to the ER for a Benadryl IV cause my throat was swelling shut.
