My 11th Wycombe Half in a row this year!
I'd agree with Stevie. Definitely worth saving energy on the first hill though as you will pay for it later if you don't. Practice a steep downhill too if you can. Nice and relaxed is the way, or your quads will curse you in the later miles!
The finish on the Rye is great, especially if its a nice day and the corwds turn up, but just be aware that you do a big loop around the park, so you can hear the comentator (and his cheesy jokes!) and feel very close to the end quite a long time before you actually get there!
Oh, and lastly - hope there's not a headwind blowing down the valley! A few years ago, a combination of the last 4 miles very, very slightly uphill and a gale force, constant wind funnelled along the valley in the face nearly finished me off!
While you're there, if its a warm day, you can take a towel and have a swim in the outdoor pool afterwards....