CN Philippines 2012.20 calculates ETA very conservatively. It starts with a very late arrival time and adjusts as you travel. This makes estimating your arrival very difficult. Roadguide does it the other way. It starts with a very "early" arrival time and adjusts your ETA based on your traveling speed. I find that Roadguide is better in this aspect. Not sure with the roads as each one seems to have a road or so not in the other.