I have 3 LFS in my town. They are all different and none of them consistantly have healthy fish. I do have a favorite store and they have healthy fish for the most part and the manager is pretty knowledgable and helpful. They have "happy hour" on Thursday afternoon and sell all plants and fish for 50% off ( normal prices arent real cheap, so it isnt like they are giving the fish away $3 for otos, $4 corydoras, $2 neons etc ). I plan to order all of my fish for my 50 gallon build from this store. They have agreed to allow me to pick up the plants and fish without them "stocking" them. So, I get them straight from the wholesaler without paying shipping and avoid them being exposed to the water at the LFS. I plan to QT them for a month in a hospital tank, I cant put them in my Aquasoil tank for a while anyway.
One store sells most of their fish for bottom dollar ( blood parrot cichlids for $5, neons, CPDs, Cardinals, Corydoras etc for $1-$2 ) They have bacteria breakouts and ich issues often enough that I havent purchased any livestock from them. They have great prices on everything though ( including equipment ) and they have special ordered several items for me for no extra charge.
The other store sells more rare fish and salt water ( they have some sort of salt water fish that has a $1000 price tag on him :O ) They also have heavy ich outbreaks most times I go in there. I witnessed HUNDREDS of dead fish ( mostly feeders ) on one trip to this store. I walked around the corner and 2 or 3 tanks were full of dead fish. The manager of this store is very nice, but Im scared to buy anything from the store.