I have had Stripe for a couple of years now and I have never had a problem processing or receiving payments. So I am happy with them.

Paypal is by the far the easiest and most pro-consumer and pro-producer for financial transactions around.

Square is so easy to use and very reasonable pricing. They only charge fees when you process and there are no monthly processing junk fees. You can also create and send invoices as well as setup an online store. Many businesses could use square to run their entire business. We have run as many as 150 transactions in a day back to back to back and it works without any issues. I have tried other solutions and run into problems that hinder running a large number of transactions in a short period of time like time outs, logging me out, slow processing, etc... I have never had any problems with square in over 2 years of processing with them. Any business could use squares solutions to make more money and save time.