Based on the latest RTW Fares spreadsheet (http://qsi.cc/users/wbt/RTW%20Fares.xls), it appears that if I'm looking to purchase an economy RTW 29k ticket, one of the better bets is to purchase it from Bangkok... (and, side note, that spreadsheet is AMAZING ... proving once again how invaluable this community is once you discover it!)

Anyway -- this is well and good, but I'm still a bit in the dark as to (a) how reliable/safe is it to purchase a RTW ticket abroad, (b) are there any hidden fees/taxes that might be avoided by purchasing in your home country (in my case, the US), (c) how can I confirm the current price of a ticket in, for instance, Bangkok, and (d) do I lose out by not purchasing and booking my flights months in advance from the US, and instead just jumping on a fight to BKK and expecting to sort everything out there?

Many thanks in advance for any advice!!