Currently using Canon 500D with kit lens 18-55mm. Looking for a walk-around lens mainly for travelling. Please give me some recommendations from personal user experience. I'm contemplating between
Sigma 18-200mm f/3.5-6.3 DC OS
Canon EF-S 18-135mm f/3.5-5.6 IS
Or any lens which are similar to the above in terms of price and comparable features.