Can't argue with an etrex for an occasional bike user especially at that price but it's a bit of a brick size wise and connectivity is pretty much nill.
Each to there own
I think you'll find that there are a lot of long-distance cyclists using eTrex gpses - people with lots of experience both of cycle touring and using gpses.
If you want the training/performance monitoring features of the 800-series gpses then the extra expense is probably worthwhile, but for *touring* they don't (SFAIK) offer you any more than you'd get with an eTrex.
The eTrex is certainly chunkier than the Touring models - but I'd guess that most of most of the extra bulk/weight is due to the AA batteries. So the choice boils down to a smaller svelte package which you can recharge with a power pack - vs the ability to simply pop in another set of batteries (or worst case, go into a shop and buy some non-rechargeable ones) if you run out of power. A 17-hour battery capacity is fine for day rides, but for touring it falls awkwardly short of two days riding.
Connettivity almost nil? Well if USB counts as almost nil. OK wifi would nice, if you are touring with an iOS device but the Edge Tourings don't seem to have it either.
If I didn't already have a gps I'd look long and hard at the new Touring models, but if you already have a reasonably current gps it's probably not going to be a huge leap forward - but we'll see