I have been on Byetta for about six months now. I had NO problems with the five pen, and lost about 15 pounds with little or no effort. I was moved up to the ten pen this month, and have had a LOT of nausea, and NO weight loss now for two or three months. I am frustrated, as I had hoped it would make a difference. (I have metabolic syndrome, and am now diabetic, so losing weight has been nigh to impossible for years) The Byetta has done great for my blood glucose levels. There is a thread in the diabetes support forum on it, where there are a number of people who use it posting. Here is the link:
http://www.3fatchicks.com/forum/showthread.php?t=87241
I carry my pen with me when I travel. I go to work at the studio of my partner about 1 and a half hours from my house every week, and I carry the pen with me with no trouble. I got the carry case from the manufacturer for free and it works great. Others use a thermos bottle with an ice bag. It is not hard, just take a bit of planning.
I hope it works well for you. To me, it is almost a wonder drug.