I've only been biking here in Sri Lanka for a few days, but thought I'd give a few impressions:
Absolutely gorgeous country, and wonderful, good-natured people. A substantial number speak some english, often fluently, which makes getting around easy. Prices are dirt-cheap for guesthouses and restaurants, though national parks and most museums charge non-locals first world prices.
The roads: Well, some are decent, and many are abysmal. I'm riding a Bike Friday. I put some wide tires on before I left. Good thing. Some of the "paved" roads I've been on here make the rough roads of Costa Rica look like freshly poured concrete.
It's a hilly, and in places, mountainous country. Fortunately, there is a half-decent train network, and many of the trains take bicycles, though not all. The cost to take my bike was nearly double what my own ticket was, but since both totaled about US$1 (for a 90 minute trip), it's hard to complain.
Superb food. Eating here is an absolute pleasure, assuming you like spicy food, as I do.
I'll try and post a full report when I return home.