I flew Air Asia twice. The first time from Bangkok to Hanoi - we left on time and arrived 1/2 hour early - really cool. The second time was from Phuket to Bangkok and then Hanoi - this time we left late and only just made our connecting flight by 5 minutes. Air Asia do not book your luggage through - they are strictly a point to point airline. So you have to wait for the luggage and move it through yourself. I had left 2 clear hours for the interchange, but being late in leaving and then the bags didn't surface for 40 mins plus the huge airport at Bangkok, we just made it for our connecting flight. I can recommend using the airline for the price and it really was very good, but I know it was far too stressy for me with connecting flights!

how limited is the baggage allowance? is it reasonable? how many pounds per person? what about carry-ons?

It's 15 kilos per person, usual domestic allowance on other airlines is 20 kilos. You can have one carry-on. Check thjeir website and see whether they have a weight limit for carryons.

Thanks Kathie. That doesn't sound too bad. For $100 BKK-Hanoi, I think that's our best option right now. And waiting on possible promotions for Vietnam Airlines. Seems awefully steep to pay $228 one way Hanoi-Siem Reap.

Even if your luggage is a little overweight, it will cost less to pay the overage than to fly on VN Air. Do check Thai Air on that route as they sometimes have specials as well.

Yep. Checked Thai Air, and that route is $338 one way! Pretty steep, especially compared to $105 .

Do you know when VA normally has promotions? Their current ones seem to only be valid for flights before Oct 30.

They tend not to have promotional fares during high season.

If you have the time and willing to spend a night in HCMC and Phnom Penh and are a little adventurous you could get to Siem Reap as follows.
Pacific Airlines flight from Han to HCMC around $50.
Bus (Mekong Express)to PP. takes about 6hrs and cost $13. Overnight and take their bus to SR. 5+hrs and $10.

A roundabout way but you do see some of the country side and the roads are quite good..

Thanks Scotters. Unfortunately, we only have 22 days for our entire trip, so we just don't have the time to take that route. How I wish I didn't have limited vacation! Travel when I was in college was so much easier.