A friend of mine, new to BKK, arrives next week, asking that question. I always have taken a cab for convenience and reasonable cost. But 8.30 AM, a cab or airport bus could hit traffic jams, especially around Siam. Train means transfer somewhere to BTS, may be a hassle with luggage. What do you recommend this week? Time and convenience first.

Airport train then change to BTS at Phaya Thai or just get a cab there. Unless your friend would like an adventure of BKK traffic.

It might not be so bad since some school already closed for the holidays, but again this is BKK.

After you land in bangkok the last thing you want is get your holiday mind straight into bkk rush our(830)am . 1000am is better so my suggestion is hangout freely at the airport drink eat smoke, etc. So the question is : is he landing at 830(that would be good) or is he walking out of the airport at 830?