We have been using PayPal for at least 15 years or more. At first I used them for non-tangible
affiliate marketing sales, and if someone decided to charge back, even after I sent them their product, PayPal deducted that amount since I could not prove delivery. I don't like them for non tangible, downloaded sales, and they are not partial to businesses they deem risky. That is their right, and anyone who complains about that will find most merchant accounts are similar.
For the past 12 years we have been using them for one of our payment options on our hard goods website (in my sig), and have never had a problem. If someone chooses to checkout with PayPal on our website, the money is instantly credited to our PayPal account, and I simply transfer the money from PayPal to my business bank account; the funds are in my business bank account within 24 hours, often sooner. This is faster than most other merchant accounts which can take a few days to deposit funds into our bank account. I also use their card reader at craft shows and for some wholesale deliveries/pick ups. Same thing, money is in my business bank account the next day. Someone mentioned their fees are high, but they are actually less than many merchant accounts used on websites. Their fee is .029% + $0.30 per transaction. (I believe, but am not positive, that fee can be less if you do higher sales volumes.) We also use Stripe for our credit card provider on our website, and their fee is the same as PayPal's. When using the card reader, the fee is even less. (All merchant accounts charge a higher fee when a card is not present for a sale [i.e. online or when the merchant has to physically input the credit card info as is the case with a phone sale] as opposed to when the buyer presents the physical credit card for swiping.) You can withdraw funds to your bank account or to a PayPal debit card, but there is a fee if you have the funds transferred to the debit card. We don't have a PayPal debit card.
I also have a personal PayPal account that I sometimes use for online purchases where a merchant only accepts PayPal. When paying, I have the choice of having the funds drawn from my personal checking account or my credit card. It couldn't be easier.
Their customer service was horrendous when I first signed on 15+ years ago...almost impossible to contact, but I have found this has changed, and would rate their customer service just as good as, if not better than, other merchant accounts I have used in the past.