I started waiting 20 minutes to eat after bolusing recently. I've been type 1 for 13 years, and the doctors always told me to eat within 15 minutes of taking Humalog--even saying I could take the insulin 15 minutes after eating.
I started waiting 15 minutes before eating, then I thought 20 minutes was better, and now I'm wondering if 25 minutes might be better still. It can be a pain, but my lifestyle is such that I generally have time to wait. When I eat out, it can be tricky. I've tried waiting the 15-20 mins with a burger and fries sitting in front of me at a fast-food restaurant and it was hellish. For regular restaurants, the wait could be 20 minutes or 45, you never know. I generally take a unit and then take the rest when the food comes. I don't eat out very frequently, so I don't have this problem often.
I agree that it can be a huge drag to wait before eating, but it certainly helps my post-meal blood sugar.
(I live in Canada, and Symlin is not available here).