I can't speak to specifics about the eTrex, but for me it's easy to merge tracks. I have a Garmin Dakota 20, and when it runs out of its 10k points per track it just starts recording to a new track automatically. In Garmin's Basecamp software, you just select all the tracks you want to merge and right-click to merge them--it will ask you to order the tracks in merge order, and then hit done.

Another nice thing about the Dakota for multi-day trips is that it takes a pair of AAs, so you can just carry spares. Garmin reports 20 hours per pair, but for me it was closer to 14, which is still much better than my phone running Strava.

The Dakota 10/20 isn't cheaper than the Edge 200, though, so it doesn't fit your price range.