I recently part-exchanged my Canon 300 f4 as I had hardly used it along with
some other kit to part finance my upgrade from 10D to 20D with 10-22.
I now have:
20D
EOS 100 (figured that this would not fetch much so also sold my EOS3 sob,
but since going digital had not used it much either)

EF-S10-22
EF17-40L
EF28-80 series 1
EF50 1.8
Sigma105 macro
EF 70-200 L
EF 1x4

Now I regret not having a longer lens! I was wondering about the above 2?
are they any good? Which is the better lens?
I rarely used the 300 as I could not always be bothered to carry it and it
not being a zoom limited its use for me.

I cannot run to paying out much and do not want to invest a lot in a lens
that will not get as much use as the other lenses. So just for occasional
use and for taking pictures of seabirds, and sometimes smaller birds.
Puffins pose quite well!

Anything else I am missing?? I can always dream! I have wondered about a
35mm fast lens as a standard lens on the 20D!

All ideas appreciated!
Especially thoughts/knowledge of the Sigmas.
Thanks

Julie