I have been trying to use coinbase as an e-wallet, but it has become totally unreliable. I tried to send some bitcoins to a friend, and the transaction has been pending for 2 days. There is no way to cancel it, so my friend and I are stuck waiting to complete the transaction. This has happened on my last two transactions. Unacceptable. Whatever the problem is, I hope they fix it soon.
Coinbase in general seems to be consistently overloaded. I've tried to buy BTC from them on several occasions, but not once have I succeeded due to the 24 hour rolling limit.