What type of travel to what kinds of locations? That can be a huge factor in determining the pros and cons of such an offer. My job requires anywhere from 5%-75% travel (though I average close to 5% myself) and it can be annoying but I get paid for my travel time and I'm normally in or close to a large city so I can do stuff. My brother travels 95% for his job but most of the locations are rural, he doesn't get paid for his travel time. That's a huge negative in my book for him just based on travel locations and what I consider "free work" in his travel.
A pro for lots of travel (if the company does reimbursement instead of just booking all your travel) are the points you can earn staying in hotels etc. A friend of mine will rack up about 200k pts on one hotel chain alone next for his work travel, but all those rewards pts will be in his personal account. My brother does the same thing. Personal vacations are nice when you don't have to pay for things like hotels because they are comped from the rewards you earn while working.