I recently purchased a EOS Rebel xti with a base lens. I was thinking of Tamron but reading reviews i decided not to. I am thinking of buying the Canon EF 24-105mm f/4 L IS USM Lens. Have any of you used this lense and what do you think of this lense. Could you explain certain terminology like What do the following mean. 1.Digital SLR with a high FOVCF 2.It is slightly long on a 1.6x body 3.A fixed f/2.8 minimum aperture makes this lens as fast as any Canon EF zoom lens. 4.Barrel distortion on the wide end 5.Vignetting is very well controlled Thanks for your time and help.