Clipless pedals once again and the Texas Time Trials

[thekarens]

I am scouring the old posts and reading all I can find on the web, but also wanted to suggestions on where to start for my specific needs/wants.

Somehow I lost my mind and let myself be talked into signing up for the Texas Time Trials. I signed up for the "easiest" race, which is 26.5 miles, which must be completed in 3 hours. Sounds easy, right? I'm sure for most of you it would be, but we don't have hills here in Houston and I know I'm not at the fitness level where I can do it yet, but I have until September to train.

Anyway, as much as I swore I would never go clipless I'm thinking it would help me reach my goal.

Here's what I'm looking for in a clipless pedal:

Road specific......at this point I don't think I will ever go clipless for MTBing. I like my platforms for that.
Ease of use - easy in, easy out
Easy on the knees - my right knee is in less than ideal shape
Best bang for the buck - ideally I'd like a shoe/system that would last

Looks are not at all important to me. I would like a pedal that I won't want/need to upgrade even if it takes me a little longer to learn.

Please tell me there's someone out there that hasn't fallen learning how to use them and if there's an article and/or video on learning it would also be appreciated. I plan on doing a lot of practice before I take "the show on the road" as the saying goes.