70-200mm f/4 IS or f/2.8 IS ver I

As the title states, I am trying to decide which I should get,

The f/4 IS for 1189 (aaefess 15% off deal) or a used f/2.8 ver 1 that I've seen for 1300-1500.

Besides the obvious stops of light lost with the f/4, I've heard that the f/4 is shaper than the f/2.8 ver I simply due to age. Anything else I am missing?

Size/Weight... The f/2.8 is much more hefty.

The f/4L IS is sharper than the Mark I... Not much more to it then that.. Just depends if you need/want f/2.8 or a sharper f/4.

honestly if you are that close, just save the extra 700-1000 for the new version 2.8. The quality of it from what I keep seeing is just phenomenal!

I had the f4IS and was never tempted by the f2.8 non IS or the IS, for that matter. Weight and the f2.8's didn't impress me at the longer end.

When the MKII came out that changed everything, for me. I bought it.

So, if I were you, which I am not, I would get the F4IS unless you absolutely need f2.8 and will be able to keep your shutter speeds up there.

I am happy with my f4 IS, I considered saving for the mkII but after shooting with it for a few days (borrowed a friends) It just was too heavy and the extra stop of light was nice for night sports. As for everyday shooting and walking around in daylight I'd much rather use the f4 IS.

It is sharper than the f2.8 mkI at f4.

If it's going to be a walk around lens (the MKII isn't for me), then I wouldn't think twice and get the F4IS.

Hm thanks for the quick replies guys.
@seahawks, I decided against saving for the ver II because there are other things I want to get for my photography goals, lighiting, backdrops, memory, books, classes, TC, etc.
@comments about speed, I am really not into sports photography so +1 for f/4. I dont need the speed, just like the DOF option.
@comments about weight and size, I see myself walking around with this lens, normally I dont care about weight and size, but in this case I think I will make an exception. I want to also use this as a portrait lens so I will be hand carrying it alot, (dont like restrictions on a tripod) so weight will really matter.

Thanks guys, I will get the f/4. If i find myself using it more than my other len's I will look into saving for the 2.8 ver II.

Ok, I wasn't sure what your intentions were for using it. Since it seems portraits is what your aiming for then I would say it doesn't totally matter.