planning on taking train from south myanmar heading north for 3 weeks......any suggestions, warnings, etc. greatly appreciated...

Are you starting from Yangon ?

stop in Bagan

In July last year took the day train Bagan to Mandalay upper class $2.90 7 1/2 hours

i took the train in March from Mandalay to Myitkyina, overnight sleeper 21 hours $23.

nice trip than flew down to Bhamo ( that part of the river is closed to westerners) an than the river back to Mandalay. via Katha

Enjoy, north of Mandalay u will see very few tourists we saw 4 in 8 days :-)

http://www.reitman-photo.com/f125862719

planning on crossing at ranong then heading north......keep the suggestions comin