Good news till you try to use BitPay's payment form that isn't supported by most wallet clients. If you find a wallet client that does support their payment form, there is no Segwit. One big mess.
Most wallets still don't support BIP70?! I guess I wouldn't know. I've been using Electrum as my everyday wallet for years now and never missed a beat when Bitpay implemented BIP70.
And then they also charge you an additional 'transaction processing fee'.
That does piss me off. They charge everyone an additional fee ~ equal to the cost of sweeping the output in the next block, but they never sweep anything immediately. I think they're making money off the "network fee" -- and of course, giving small blockers the middle finger.
The other thing that pisses me off is their refund policy. Whichever direction the price moves, they screw you on the exchange rate. If the price goes up, they give you less coins back. If the price goes down, you get your coins back -- minus another "network fee" of course.
Someone on Reddit suggested that you can top up your ATT account through Bitrefill, which accepts both main-chain payments and Lightning payments. Not sure how it works since I'm in Europe, but if it offers the same functionality, definitely use this instead of BitPay.
I'm not positive, but I think that only works for prepaid phones (not bill pay). Bitrefill also charges obscene markups on a lot of their cards -- and seemingly no markup on others -- so it's worth looking closely at the price.