The commercial grade EZ -UP is the only way to go on this one.... Get the heavy duty version with VERTICAL legs. Equip it with some 10 inch spikes for staking or 4 5 gallon buckets filled with water and you should be fairly bulletproof.
Be prepared for some sticker shock, these baby's are not cheap. I have used them frequently for Famer's Markets's and have recieved almst 4 years of bi weekly use out of a single unit, and I live on the coast...
Save your mney and spend a bit extra. You might also find someone who uses these for festivals, farmer's markets, or other outdoor events willing to let an older one go for a few dollars.
If I could do it all over again the Run a Muck tents would all be vertical leg ez ups...