http://www.westcoasthost.com
They aren't big in adult yet, but host at least one very big name. They are launching an adult-specific hosting company in the next few weeks. You'll see the best pricing available, especially on bandwidth.
Example: My virtual hosting with them was a reseller account, $29.95 a month, 1000 gb transfer, unlimited domains.
My dedicated is P4 1.8ghz, 80gb drive space, 1gb memory, 1200 gb transfer with cpanel, etc, for $129.00 a month.
If you want to get hosting from them, call them (800 number on the site), ask for David, and tell him primanudes.com sent you. He will hook you up with an unlisted pricing deal. For the best deal, be sure to mention primanudes.com sent you - no joke. We're friends from St. Petersburg, Florida.
He's told me his pricing for unmetered bandwidth, but I can't recall. It beat everything I looked up.