Like many others, have a Mio P550 running TomTom 6,Memory Map 5 and Beeline.
TomTom is great for getting to a parking location as co-ords can be entered directly.
MM is good for seeing where you are but I am still having teething troubles with showing waypoints.
We still normally use the good ol' etrex for the final leg as it is rubust, waterproof, clear and batteries last for ages.
Not only that, son and/or daughter can run on ahead with the etrex whereas I wouldn't want to risk the mio getting dropped or argued over etc...
Being able to set cache locations as tomtom point of interest is really handy and enables us to spot caches which we would otherwise have driven straight past.