Rayman:
If I may suggest another option, I just got a Delorme PN-40 back in December and love it. Previously I was using a Magellan Explorist 500. It was nice, but the Delorme blows it away in my mind, hands down. The price is usually around $300 on amazon.com and has true paperless geocaching features. It comes with Topo USA 7.0 (version 8.0 is scheduled for mid-May and the GPS ships with a coupon for a free upgrade) to give you topo features, major trails, and road routing. With the new firmware upgrade, I can use the Send-to-GPS feature for single caches, and their upcoming geocaching widget will allow me to send a whole query
For an additional $30, you can get a subscription to Delorme's map service giving you access to B&W and color aerial imagery (1-meter resolution) for nearly the entire country, high-res imagery (1 foot resolution) for select major cities, NOAA coastal water maps, and USGS quads. For the color imagery, think of having Google Earth on your GPS. It's way cool! I'll also mention that their tech support is second to none. They are very active on their own forums and also participate in the geocaching.com forums.
That sounds cool, but does it do WhereIgo? I'd really like to get into that.