Pros: Great zoom range, multi purpose lens. will do most anything a beginner photographer would want to do.

Cons: zoom creeps really really bad I have to keep my hand on the zoom ring to stop it from moving while shooting. May be my lens though as it has got a lot looser since I first started using it. If I point it at the ground it falls down to about 170mm. quite soft, can be slow to focus in lower light.

Other Thoughts: This was the kit lens I got with my 60D. I loved it at first but after a few months started to be unimpressed with its sharpness. It is not a bad lens just not great. I would have been disappointed if I paid retail price for it. The IS is very nice, I can shoot hand held down to around 1/5 at 18-24mm and 1/15 at 200mm with very little blur even in low light. I am not sure the sweet spot in the focal range but it is really soft at 200mm.

I would give it 3.5 but thats not an option so I gave it 4.

Pros: A range of 18-200 creates a one lens camera for most shooting. This is a lens that could possibly replace all your other lenses as long as you don't need super super high quality. I shoot mainly fish on the top on a tower in sometimes heavy weather. With 5ft waves that are exaggerated because of height (imagine the spotter on sailboats) the boat can rock back and forth a good amount. This makes it very hard to switch lenses especially if I'm trying to hold an umbrella as well. In final one lens is a necessity for me.

The overall quality of the lens as far as i can tell (shot about 1000 pictures so far) is good and stays good through out the 18-200.

Cons: This lens as a super range lens will of course have some negatives, but all of them are minor unless once again you need the best of the best in a certain area.

Sharpness is probably the worst part of this camera, but so easy to fix in photoshop its hardly a con. The focus isnt super fast but still fast. I forgot the word for it but the lenses weight will pull it down. And finally the price isnt the easiest to afford.

Other Thoughts: A had to debut weather to give this lens a 4 or 5. I decided with the 5 mainly because I'm only using an xti and think this lens would improve with a better body. In summery its a great all around lens the only thing i could add is there are better options out their if you have the time to switch lenses. For what i do it is a necessity though (without having 2 cameras/lenses) and it has earned my approval.

Pros: A great lens to bring along if you only have one, because it offers a nice range of focal lengths. I've brought it on many trips.

Cons: Disappointing quality. I'm fairly active and this lens goes with me on many outdoor activities. I've had to take it in for repair twice, when there has been friction with zoom in/out, and the lens lock functionality failed. I expected better quality from a lens at this price point.

Other Thoughts: I do not recommend this lens - I recommend saving your money and buying a higher quality lens.

Pros: Huge zoom range (10x), image stabilization, 1/3 stop faster than competition from Sigma & Tamron, decently fast focus, astonishingly good image quality for what it is (an inexpensive 10x zoom for use on DSLRs).

Cons: Zoom is a little loose (have to use the lock to keep it from self-extending when hanging down), lens hood not included, some chromatic aberration.

Other Thoughts: Bought this for a trip to Disney World, where I wanted the image quality and convenient operation of my EOS 40D without having to drag a whole bag of lenses with me. This lens was completely up to the task, capturing four days' worth of photos without a hiccup. Covering wide-angle (though not superwide; the 10-22mm USM is unbeatable for that) to telephoto, there are very few shots you can't get with this lens. It's not going to take the place of my primes, but it's better than several other zooms I own.

Pros: Zoom range, excellent IS, accurate AF (not USM, but still fairly quick and quiet)

Cons: Corner performance is a bit weak unless stopped down. Lots of barrel distortion at the wide end. Vignetting at the long end is noticeable in open sky shots, etc. unless stopped down.

Other Thoughts: This lens is impressive given the super wide zoom range. I think it gets unfairly knocked in some online reviews/forums. It's not a prime or L lens, but for real world photography (not pixel peeping) it does a lot of things well and is great for those times when you don't want to carry a lot of gear.

Pros: I used to carry around a couple primes and a zoom lens but this thing makes them feel unneeded. I use this with my 50D and Ive not yet been disappointed in the great variety of magnification. The lens is not a lightweight if you normally carry around a 50MM prime but for the high quality build and to have IS built into it the weight is reasonable. I don't know of any lens by canon that's more versatile.

Cons: you can find reviews stating its weakness in distorting in the maximum and minimum zoom levels but in all reality they are very minimal and I have to zoom in on the images over 100% to even begin to notice any curvature.