When I lived in the Chicago area, a local TV station did a test of various mosquito units. As I recall, they found these units to work real well.
On the down side, they were expensive and expensive to run. They found that the bug zappers not to do as well (I’m digging this out from about 3 years ago, so it might not be real accurate). Also, the one thing I remember is that products like “Bug Free Backyard” work almost as well and are very cheap comparatively. You do have to apply them every 3 weeks or so. I’ve used this stuff in the Chicago suburbs and have been very happy with the results …. probably poisoning me and everything around me. Read more @ http://groups.google.com/group/alt.home.repair/browse_thread/thread/8719fff70f4b9ff6/33842544ca41db0f?lnk=raot