The Utility Lens (or the "Mom lens")
A lot of folks have asked, "What lens can I buy that will kind of cover all the bases and one I will not have to change all the time.
The answer is and has been the "utility" lens. It was originally introduced by TAMRON back in 1992, as the AF 28-200mm f/3.8-5.6 LD. It has since had a digital redesign and face lift, resulting in one of the best ones on the market ... now, this is a mouthful but here it is:
AF 18-250mm f/3.5-6.3 XR Di-II LD Aspherical (IF)
After doing some rather extensive testing on my own, the images that result from using this lens are on par or better than any other lens of its kind. It runs about $450-500, depending on where you get one, but it is handy as heck for vacations or just running around, when you cannot keep your assortment of glass at your side.
Now, there are some things about a lens that has this broad a focal length. It really is more like an 18-135mm, when your subject is standing 10-feet away. If they get to 27 feet away ... because of the focus adjustment, it effectively extends the focal length to the advertised 250mm. You really have to witness this to appreciate it, but that's the way the lens works.
It also shoots a little darker after 70mm, because of the f-stop drop that occurs in a longer tube. If you are outdoors, it usually is not an issue. If you telephoto indoors ... better have an external flash handy.
Once again, this is the convenience lens (the "mom" lens) and is the grab&go alternative to your lens case. It's not perfect, but its not bad, either. A far cry better and brighter than most kit lenses (18-50/18-70).