Yes, the owner is 'eccentric', i.e., not exactly gregarious. But what's that matter if you're looking for a good place to sleep and chill. Rooms are great and spacious. Place is kept quiet most of the time. Far enough away from Khao San to enjoy atmosphere of local lifestyle. Access to everything you need. Reasonable prices. And it's situated in Banglampoo (sp.?), which is a much more interesting neighborhood than Khao San, though Khao San is only a short walk away as well.
For all the above reasons, it became my go-to place. Now, partly because of my stays at this guesthouse, I'm three days away from permanently moving to BKK. And I'll likely stay there again for the first few days, while I figure everything out.