I have been to Chimuri twice -- once in 1997 and then in September 2009. I had remembered it being beautiful, relaxing, removed from the town and I had the beach all to myself; this visit I found the same to be true, even though the town of Puerto Viejo has grown quite a bit in the last 12 years.
Mauricio and Colocha are excellent hosts, providing us access to filtered water (so no lugging bottles from town or purchasing a bunch of plastic ones) and having a cleaning lady come every few days to keep the houses clean. With the full kitchen we were able to cook most of our meals ourselves -- don't miss the weekly veggie truck! Great produce for even better prices.
You can easily rent bicycles either in town or up the road at Banana Azul and it makes getting to/fro Puerto Viejo very easy for shopping, discos, bars, restaurants, etc. But you're also very removed from the town, which I found quite lovely, and you're right in the midst of the jungle but by the sea.
I really love it here and will definitely plan to go back again -- much sooner next time!
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC