I had a very good experience with them. I ordered Herichthys pantostictus and they arrived in perfect shape, exactly as ordered from the Florida facility.
Shipping in general is a very touch and go process, and very stressful for any fish.
If a package is handled roughly by the airline, or if the package sits on the tarmac in a wind chill, or hot sun too long, these all can effect the end result.
If the fish is not properly acclimated, or quarantined, this effects end result.
If a shipment arrives dead, take photographs in box, with label showing.
Always use overnight, and I always have the package sent to my local post office (if using USPS) with instructions to call me on arrival, and I come there to get it immediately.
There is nothing worse for fish than riding around in a cold or hot truck all day.