It seems to differ between implementation. In Iceland the readers have usually been superfast. We just had a Costco open and the readers there are superslow. Goes through multiple handshakes and notifies you of the process. They might be hooked up to a different payment processor than the local ones, hence higher latency.
That's odd. My costco recently switched to using chip readers and they are SUPER fast. They're the fastest I've ever seen. I can't imagine there's any way they're contacting a host at all...
