The problem with Venmo is that, as far as I know, both parties need an account in order to transfer funds, especially at the lower rate.
I have been using it on and off and now I prefer https://ribbon.co/ (not sure if just anyone can sign up, I got early access). Ribbon lets you pay people even if you don't have an account at standard rate for credit cards and free with debit or bank. You can also pay someone else with Ribbon and the other person doesn't need an account to accept money.
That looks great as well! After reading the FAQ, it says there are limited account spaces and there is a waiting list to get accounts.