I called the bank today, and the banking rep mentioned this add-on feature which is not described on the website. According to the rep, withdrawals are allowed to reduce the balance below $25,000. The rep also said that out-of-state customers are accepted. Accounts can be opened by mail. They have an online application, but signature cards and copies of ID may need to be mailed or faxed. I would recommend contacting the bank before applying for the CD online. The rep said this promotion should last for a couple of weeks, but as is typical, there's no guarantee.
Branches are located in Dallas and Plano, Texas. The bank has been FDIC insured since 1934 (FDIC Certificate # 29209). It has a 3 out of 5 star rating (performing) at Bankrate.com based on 12/31/07 data.