Canon EF 90-300mm f/4.5-5.6 USM

Any opinions on this lens?

http://www.amazon.com/Canon-90-300mm-4-5-5-6-Autofocus-Telephoto/dp/B0009X6RX2/ref=pd_bbs_sr_1/104-4010566-7687927?ie=UTF8&s=electronics&qid=1178728334&sr=8-1

I know its cheap, and slow. But other than that?

Optically it is similar to Canon's 75-300 lenses. You can find a review here:

 

http://www.prime-junta.net/pont/Reviews/db_Canon_90-300_mm/a_Canon_90-300_f4.5-5.6.html

I believe it's got a plastic housing (may not be too resilient to bumps or falls).

If you are on a budget, look for a used 70-210 3.5-4.5 USM. It is small light, build quality is good, has fast ring USM, and optically it is a class apart from all the 75-300/90-300 consumer zooms.

This budget (rather than 'consumer') lens was designed down to a price for low-end Canon film SLRs, presumably on the expectation that drugstore-quality printing of a full-frame negative to 4-by-6 was the toughest demand likely to be placed on it. So the review linked to by Mark U should not be a surprise - Canon's DSLRs, throughout the range, have long since outgrown this type of lens. But that certainly doesn't apply to all early EF lenses, and particularly not to the prime lenses, most of which are still with us. My Compact Macro 50/2.5 wheezes a bit, but it still delivers the goods in terms of image quality.