I don´t do geocaching, but I have a SE W760i and I think it´s quite an interesting GPS device, even though way inferior to the Oregon 300 in many aspects.
Drawback examples in my opinion: battery life, ease to scratch/damage, satellite acquirement time too long (sometimes it´s actually fast if aGPS is used), sensitivity not that good (I´d say it´s between the Oregon 300 and the old eTrex Euro), update rate so lazy (even configuring it to update every second, in one of the maps application that I installed in it).
One thing that I like about it: versatility, such as the ability to install several applications (satellite imagery, fixed maps - or a mix of both, vector maps - either online (paying for Internet usage) or offline (putting everything into the memory card), record tracklogs, speed limit alerts (visual/aural) and a few others.
Rgds,
WF