What exactly are you looking for? What kind of features would you like? For me, my old Garmin eTrex Venture Cx is more than sufficient. I'd like to replace it, but have a hard time justifying it since it works so well for what I use it for on my dirtbike to record my track for the day. Top speed, avg speed, total distance, in addition to the tracks are all nice to have features for me. However, I don't ever really use it for the mapping per-se. I'll occasionally use it to mark key intersections or key points...otherwise I think the handhelds are really too small to effectively map with (for vehicle use). It's get me out of bind and lead me to where I needed to be if the occasion arose.
As for units, etc...you can't go wrong with Garmin but Delorme has some good looking screens and mapping. Delorme also has some neat features on their nicer units (like spot integration). The downside to the Delorme units is their battery life is no where near what the Garmin's are. My Garmin will last half a season of heavy use. The Delorme's will get you about 6-8 hours of use on a set of batteries.
When you decide on a unit, hit me up and I'll see what I can do for you. I can get most of the Lowrance (another high quality mfg) handhelds, most of the Garmin handhelds, and all of the Delorme handhelds.