Should I buy Canon only?

Get the kit lens to start with, and learn to use your camera and basics of photography. Then you will start to figure out what you want, longer or more wide angle. I have gone longer for wildlife, and bought quality L lenses, not a single regret. HOWEVER, I am looking at the Sigma 150 f2.8 macro, it is highly regarded as a macro lens. I currently use my 70-200 f2.8 with a set of Kenko rings for macro work.

Canon are great, for sure. But, if you only get Canon, you are missing out on so many other great lenses. See my gear list for example.

I am a relative newbie, but I have been watching the buy/sell posts here and on Fred Miranda. What strikes me is the way genuine Canon lenses hold their value. Compare it to a Honda vs a Kia. They are both nice cars, but when you go to trade in the Kia you will be shocked on how little you get back.
All that being said, I recently sold my Canon 17-85 IS and replaced it with the Tamron 17-50 2.8 primarily for the speed and sharpness. It was very easy to sell the Canon. And I really like the Tamron. Canon has nothing this sharp and fast under $1000.

I think it's a matter of budget as well, if you can't afford a canon L-lens most of the time you'll be better off with a sigma-tamron-tokina rather than with a cheap canon...as easy as that, I'm a satisfied sigma lenses owner, both the 17-70 and the 70-300 permorm incredibly well for the price, the latter u can find for as cheap as 89 pounds on some websites....the first I bought for 130 pounds new!!! I won't tell u how....:p

mzivtins wrote in post #5215802
i dont think the manufacturer really matters. but just always get the best lens you can afford, what ever company give the best for the buck will win but this means you wont waste money in the long run constantly upgrading lens

Ditto. I have all Canon right now, but didn't purposely plan on it, just happened. I'll see what happens when I consider a lens around 30-35mm. The Canon one I want is very expensive; the Sigma one is good and reasonably price.