it really hurts to snort. Also, you can get high without an maoi via snorting or eating it, however, the dose required is quite large and generally not at all cost effective. Definately smoke it unless you know what your doing with maois.
EDIT: You can IV it very successfully without an MAOI. This is certainly the preferable method to smoking. You need to use less DMT and the effects last longer and are generally stronger. However, most DMT I have seen in Aus has come from 'crude' extractions and is by no way safe to IV. If your going to inject, make sure it is extremely pure (crystal). If it is a brownish pastey/crystally substance, then smoke it. I wouldnt IV either if you've never done that before. However, if you had more or less pure DMT then IV is def the way to go, as smoking DMT is not entirely pleasant (the smoke of course, not the experience).
Effects i find are very similar to a HIGH dose of MUSHROOMS. the peak tends to last from 5- 15minutes, depending on dosage. After effects could last from 10min to an hour or 2. Generally tollerance does not occur, so you can continually dose again and again. However, the more doses you have, the more the after effects linger, until it builds up to the point that you feel pretty weird until you can sleep if off. (This is all based on smoking DMT WITHOUT a MAOI)