They just changed the rules in the middle of the game by adding a "I acknowledge that the amount of BTC I receive will vary based on future exchange rates." checkbox on the "Buy Bitcoin" page. Now you will receive only what they think you should get, not what you paid for. Nice deal for them.
This isn't true. That checkbox is only relevant if you want to buy BTC and they've hit their daily limit; it means that you'll get BTC at whatever the current exchange rate is when your ACH bank transfer clears. Unfortunately since that "buy at a future rate" feature was sort of a recent hacky fix, I think you might have to check that box even if you're buying BTC locked in at the current rate and it's irrelevant -- but I'm not sure about this.
Don't use coinbase.com. Their transactions can take days in or out or even say pending for days then just not go through and disappear..definitely not reliable and it was not really meant to be a wallet service but more of an exchange. I like blockchain.info now for reliable transactions for paying and receiving BTC.
This is also misleading. Sell transactions are pending for 2-3 days because that's how long it takes on average for an ACH bank transfer to go through to your account. Purchase transactions are also pending for 2-3 days because they're trying to make sure your ACH bank transfer to them clears without error. They have to do this to mitigate fraud, as they're dealing with exchanging USD via a reversible payment
(ACH transfer) for BTC, a non-reversible payment -- very risky for them. As for orders not going through, there have been issues with this but from what I've seen it's fraud-protection related and they are fairly responsive support-wise on this.
You have to remember, Coinbase is still in beta. It's not meant for fast purchases -- it's meant for easy transactions using a linked bank account, at very low fee %s -- 1% + 15 cent flat fee.
What about using coinbase for bank account withdrawals? Does anyone have any experience with this service?
Yes; I have done this and it works fine. You can verify your bank account via the same method that Paypal does it -- they'll do 2 small under-$1 deposits to your account
(which take 2-3 days to go through) and then ask you what those amounts are
(your knowledge will prove you have account access). They also offer an "instant" verification but this requires you to give them temporary login access to your bank account, which in my opinion is not worth the risk, if they ever have some sort of mistake in the way they wipe that temporary session. I suppose you could do the instant verification and then change your password right afterwards. In general though, it's extremely poor security practice to ask your users to provide passwords to other things, no matter how convenient it might be for them.