I like Jos A Bank for their no-iron dress shirts. I shop there already knowing what I'm looking for, typically taking advantage of a sale opportunity, like my last visit when their Traveler dress shirts were 3-for-$99.
The times I've been to this store at Legacy Village and their Tampa, Florida store I have found the associates to be very courteous and helpful. I won't go to any store when it's crazy busy, so I've only been in Jos A Bank when it's been moderately busy at worst. The experiences have all been good. I've purchased several sportcoats from them, so not just dress shirts, and the sportcoats required being properly fitted and buttons changed out. The service was good and I was pleased with the results.
My only complaint with this store is with accessibility. It's tucked away in the village and unless you know where to park, it can be a bit tough to find.