I have used the Zoom fairly extensively for 18 months, and never had a problem with lag (or the switches for that matter). I personally find the EQ a bit crap, and the fuzz/distortion way over the top, but on the whole a great piece of kit. Very solid and reliable.
I tried the Pod, but found the constuction worringly flimsy, although a majority of sounds were quite nice.
I went with the Zoom, based on the solid construction, and greater array of sounds that I personally liked.
Yes it can be a bit fiddley at times to dial in the peramiters that you want, but it soon becomes quite intuitive. There was a post with a link to a site with some interesting patches [url="http://basschat.co.uk/index.php?showtopic=82984&hl=zoom+patches"]here[/url]
....and to think I used to have everything I needed in a WEM Copycat, Vox Crybaby and a Univox Super Fuzz.