Moving in to an old condo in Chiangmai. According to the true hot spot map, I am within 50 meters of a hot spot. I'm on the fourth floor. That would be cheap, as in 1000 thb for 5 months unlimited. 3B would be 590 per month. Will I be able to get by with true?

Just buy a month wifi and try before buying 12 month contract 3bb!

Yup ^^^. Only you will know if the quality of service is adequate for your requirements.

If you expect some quality I'd recommend 3BB since you'll got dedicated line (Ethernet), and dedicated dynamic IP address (6k ports available)

but True wi-fi is super cheap. (go with this option if you not use Internet that much. you'll got internet through NAT wi-fi router so the ports available and bandwidth is questionable)

I think you quote 1000THB / 5 months from this page

http://www.truewifi.net/2011/buy_wifi.htm

but if you look carefully there is another interesting page here

http://www.truewifi.net/2011/buy_pack1.htm

If you use their mobile phone service as well you'll got True wi-fi at 100THB/month

even if you not currently use their mobile network the sum up of all costs are certainly less than 200THB/month

You can also find some WISP router (e.g. Tenda A6) to NAT True wi-fi if you have multiple devices. (If you know how to set it up)

So my suggest is to try True first then if you not satisfied gowith 3BB.

i would opt for dedicated over wifi, but not knowing the area its a crap shoot. certainly cheaper to try wifi first. but way more to go wrong there