it sounds as if you must use the chip and cannot use the swipe if there is a chip in the card. is that true?
If you are using a chip card reader, and the card has a chip, you must use the chip.
If you are using a mag-stripe only reader, you can swipe any card.
If the transactions are excessively slow, what happens if you put it in offline mode, and process the transactions when you get back to an area with wifi? (How many clients have their transactions not approved in a given sale day?)
I will say that people do become accustomed to a few extra seconds on the transactions, but there is an adjustment period. Also, the transactions do get faster as they work out the bugs in the overall technology.
For the Square chip card reader, you cannot do offline mode. The Square system will only allows offline mode when it cannot detect an internet signal. And because the chip card reader doesn't connect to the app when there's no internet signal, there's no way to capture offline transactions.
The Square offline mode does still work with a mag-stripe only reader.
Bottom line for Square users ... always pack a mag-stripe only reader as a backup.