Gotta tell you. I have 4 BTC transactions on the Blockchain that have been unconfirmed for over 4 days, even with paying a modest fee.
Since the surge in price and interest in BTC, it has proved that the infrastructure can't handle every day payments. Sending $5 will cost you $5 in fees to get the attention of miners.
Bitcoin has a long way to go before it can be adopted for real life, every day transactions. No way I'd release a product or service until the payment is firmly in my wallet.
Yes, and that could very well be the fifth problem!