I am considering getting the Cateye CD300DW wireless computer - BUT, I ride on the W&OD bike trail in Northern Virginia, which means much of my riding is under high tension power lines (and some cell phone towers). The interference makes hay with my HRM (according to it, I am intermittently either in need of a defibrilator or flat-lined), and I am concerned this computer is vulnerable, too. [FWIW, the manager at the local Performance Bike store just off the trail says the Cateye has this problem.]

Anyone have experience with this computer, or alternatives with cadence, that seem to be less succeptible? (Or I'll just stick with my wired computer, although the Cateye has other features I like.) I'm curious about the Ciclosport and the Polar 720 (although I already have a HRM, it's more $ than I planned to spend, the cadence sensor is extra, and I would prefer a rear wheel speed sensor so I can also use the bike on my trainer).

I think with that much electromagnetic interference, you will see problems with anything wireless. Heck, enough interference, and even a wired unit may see some problems as well.
I have a CD300DW, and have yet to see any problems like you mention. However, I don't think I have any huge power lines in the areas where I ride.

I haven't had any problems with mine either, even in areas where my HRM gets messed up. I'm sure it will happen at some point though.

I had problems when I first installed it, and called Cateye. They suggested that I change the discreet code, which is easily done. Ever since doing that, I have no interference problems, and I love the unit. I've ridden with mine for almost 4000 miles, and it is great.

im in the same boat as CAAD5. no interference on the CD300DW (well, very little) when my HRM is getting interference from high tension lines.

I'm using the same computer, but no HRM. I've had some problems with the CD300DW, but never anything I could blame on anything other than operator error (do-oh, how did that magnet get flipped around? No wonder I'm not getting a reading on distance or speed ).

Guy in the bike shop recommended Cytec C10+ wireless because it supposedly does not get as much interference as the other wireless computers. And it looks really smart. So like a true sucker I bought it for the will-arrive-this-week new bike, even though I'm really happy with the cheap cateye I have on the other bike. Will report back if it's any good, but would welcome any feedback if anyone has ever used it. Search of the forum didn't come up with anything much.

I'm glad to hear yours is working well. I put one on my Equinox and later removed it because I help having trouble with either the speed or cadence dropping to zero and no, I wasn't coasting when the cadence would drop to zero . Is the discreet code you mention the code that is used when you synch the display with the speed/cadence sensor?