I've used both and like some things about the Tascam, especially the the line/mic switch, the locking XLRs, and light weight. One problem with the Zoom is that the mic inputs are very sensitive, and I've had several occasions where the audio from a mixing board distorted because I couldn't lower the input enough. I thought the Tascam would be a good solution because it has a mic/line input switch to attenuate the signal.
But I ran into a separate problem with sync drift on the Tascam after an hour of recording. You can see the details here:
http://wp.me/p2gorK-1I
So I still use the Zoom, but run the signal through a Shure portable mixer first so I can get a real mic level output to the Zoom.
Hope that helps
--Paul Kagawa
Website:
http://www.paulkagawa.com
Blog:
http://www.paulkagawa.com/blog
twitter:
@paulkagawa