Trading my Canon 17-40mm for Canon 70-200mm Non IS? Good trade?

[NedM]

I bought my 17-40mm for $400 off Craigslist and I've decided to trade it for a 70-200mm Non IS from a seller on craigslist.

I originally planned to sell my 17-40mm on Craigslist for about $700 and use that money to buy a portrait lens. (85mm, 70-200mm, etc..)
I have APS-C sensor camera, 600D, and I find myself barely ever using the 17-40mm because I just don't get a wide enough angle.

I shoot more portraiture than landscape and I could always use my kit lens 18-50 in case.

So I'm guess I'm asking this:
Would this be a good investment to trade my wide angle lens for a telephoto lens that I would be using more?
I just need some second opinions.

 

[JohnTrav]

what 70-200 is it? f/4 or f/2.8? canon 70-200 f/4 you see all the time sell for about $450-$500. If its a canon 70-200 f/2.8 then yes that is a darn good trade.

 

[vimwiz]

That is really expensive unless its the 2.8

I got a 70-300 non-IS f4-5.6 for like £40 used in a pawn shop.