Best way to buy bitcoins

I've been mining bitcoins for many months now, but not at rates that allow me to invest in them as rapidly as I'd like. I've recently been trying to move money from a Bank of America account to Mt. Gox through Dwolla to buy BTC, but it's been a real hassle. Funds were tied up for several days trying to get them even into the Dwolla account, and now it's requesting an account with a 30 day history since the last deposit before I can send MY money to Mt. Gox... not a good experience.

So, my question to the more established members of the BTC community is, What is the best way to buy bitcoins? I've seen a lot of references to Bit Instant; is it a good, reliable, reasonably cheap, reasonably fast (i.e. <24 hours) process?

Also, in a related question: there are a million and one websites where I can find something I want, place an order, fill out my credit/debit card information, and then they send me the stuff; charges show up on the account in minutes. Why doesn't something like that exist for BTC yet, or if it does, where is it? Seems like it would be pretty easy to protect against scams, too. Once the website has enough traffic, it will be trusted to actually send the coins (and can prove in the block chain that coins have been sent), and in order to initiate an order you have to give your full name, mailing address, etc. to validate the card. It'll have fees associated with using credit cards which would have to be passed on (in some way) to the customer, but I'm sure there are people who would pay that convenience fee.