A good Travel zoom at a reasonable price

Let me begin by saying I am not as technical as the 1st reviewer so this is a bit of a subjective laymans' opinion. I had an old heavily used Canon 28-200 that was decent but showing some age since it did not zoom very smoothly. I guess I could have sent it in for service but I thought it would be nice to get a wider "all in one" travel lense. For my purposes the Tamron 18-200 fit the bill. The opinions on Fred Miranda and other enthusiasts sites indicated the performance was steller and at this price it served in substitution over a vast range of other lenses. So - after inspecting one at a local camera store I decided to investigate further - and in the end purchased one used from an online auction site. As luck would have it I was able to meet the seller and inspect the lense prior to paying. It looked absolutly brand new and fit the description presented by the seller. It was originally purchased from a reliable big name seller. SO - in initial use I was shocked to find a #1) it focused FASTER then the Canon 28-200; #2) The focus was much sharper AT TIMES compared to the 28-200. #3) it seemed to miss focus more often then the 28-200. More on this - especially #2 on sharpness. I have rarely achieved the sort of tack sharp 3D images given by the Tamron compared to the Canon 28-200. This was astonishing. but on the other hand I was initially perplexed with the missed focus on several shots though. I have since been more careful to watch my focus points and now it seems to focus correctly all the time. I'm not sure why this is the case - maybe the Canon zoom functions better with my 10D - I don't really know. So - aside from that - I can only say this is a very good performing lense once the focusing issue was contained. Oh yeah, the sound of the focusing motor is very quiet but it does sound different compared to the Canon USM motors which generally are near silent. AND, the plastic mount does not bother me as the cute sales girl at the camera store explained - that right behind the plastic face of the mount is solid metal. I can easily recommend this to anyone with an APS sized sensor who want the absolute widest single zoom lense to carry which is also ultra-light for travel convenience.