for speed, I prefer bitcoin, for security I choose paypal as absolutely safe
Everything is advantageous in one or the other form. Here when we think of bitcoin it has the fastest transaction as well high security. Likewise PayPal as a payment service provider has got few more guaranteed return services.
Paypal is more popular and enjoy more users but things will change in future when people will be well aware about the bitcoin and they will surely switch to bitcoin looking at the benefits attached with it.