has anyone here tried both these lenses? if so, can you compare sharpness, focus speed and accuracy and overall image quality between the two? if you own only one or the other, please tell me about quality and the shooting experience with it.
I haven't had either, but I would probably go with the F/2, usually lenses aren't the sharpest fully open. So if you can step the F/2 lens up to 2.8 it might be sharper.
I don't own either of these lenses but I agree with Phil but for a different reason, when you have a lens that has a larger aperture range compared to a similar sized lens with smaller aperture range, the larger aperture allows for more use of that lens in lower light situations eg. heavy shade where the use of the smaller aperture will require the need to change ISO, slower shutter speed or introduction of more light on the subject. My next suggestion is to go to a store that stocks them and try them on your camera and see which one appeals to you or hire them for a weekend and try them out, hope this helps
While I haven't used either of these from what I understand they both perform well in regards to sharpness (stopping down of course will help as stated above wide open is usually a tad soft). Since they are both IS I'm not sure that its really a big deal about how much light you let in as hand held shake issue of slow speeds probably won't be a big factor. So the 2.8 is an STM and macro, and a crop sensor only lens. It is also cheaper. For me, I would also pick the 2.0 since you get an extra stop to work with and it seems it performs a slight bit better in regards to image quality. I also noticed that the bokeh seems to be a bit nicer.
You can also rent the lenses here: https://www.lensrentals.com/rent/canon-35mm-f2-is-usm https://www.lensrentals.com/rent/canon-ef-s-35mm-f2.8-macro-is-stm The prices are alright for most things, although some things it's better to just buy than to rent..