[Richard Fairbanks]

Before you skip delays for the speakers, you need to answer the following:

Will you ever layback to video tape?
Will you ever need to view video+audio from anything other than Pro Tools? (such as DVD player, broadcast TV)
Are any of your speakers a different distance from the mix position than any others?

If you can answer NO to all three questions then you can advance the video. By the way, have you checked the price of video delays? 4 frames of standard def composite delay is not too outrageously priced, but anything other than composite video is far more expensive than audio delays. High def video is going to be unavoidable very very soon.

The Tascam will give you up to 50ms of delay for each individual channel, which may be enough (many projectors are less than two frames of delay, but not all). If you go with digital EQs you can get delay AND room EQ. Not super cheap, but really useful. Some would say essential.

The only downsides of speaker delays are sound quality (usually not an issue in post) and realtime things such as overdubbing a music track in the control room, or talkback bleed-through in the cans (can sound kinda weird in the cans). For post, these are issues that can be worked around by turning the delays off while recording.