Great information here guys! That clears up pretty nicely. So it looks like TAILS is the best method and safest then? If LE ever come a knocking just flush that usb bad boy down the toilet.
Yeah, it's the best out of the box solution.
Keep no records on your computer(like that idiot kid that got busted in AU who kept a written ledger of all drug transactions lol) or in your house and don't be an idiot and keep your house clean if your a vendor.
And be very careful about using mobile phones. So many cases that I hear about where people get busted, a lot of evidence is found on their phone. Even if it's purchased anonymously and the storage medium is encrypted, there's a saying that metadata in aggregate is content. The records of who you called and when and from where tell a story. Really, if I was dealing and had to use a phone, I would change it all the time. That way if the shit hits the fan, they only have records for the last phone, which would go back a short time.
Also if and when I start vending I won't use my home computer for such things. I'll just a laptop and roam for wi-fi or find an a wi-fii that has a WEP key and break into it. Of course I'd have to change my mac address or just buy a cheap second hand laptop with cash and good to go. =)
I would be careful about hacking other people's wifi, because it could get you in trouble for reasons unrelated to dealing, but that could compromise your whole set up. Don't break anymore laws than you have to.
Between hiding your Tor use with a VPN or bridge, and accessing Tor through public wifi, I think the options are about even. There are trade offs to both. Sure, a determined adversary could work with the VPN provider to unmask your Tor use, but they would have to know which VPN provider to contact about which IP address. It is unlikely you'd be identified behind a VPN through a fishing expedition, although there are attacks that LE could do to identify vendors, see here:
http://dkn255hz262ypmii.onion/index.php?topic=159722.msg1129048#msg1129048
Public wifi is a good way to guarantee no Tor use is linked to your home, but there's a really high chance that you will be on camera. Even back alleys have security cameras these days, and if you want to sit in a store or some public courtyard or whatever, you will certainly be on camera. That could be dangerous if someone links your activity to that spot.