I'm not too concerned about rattling since I rarely get to listen to anything at concert volume these days (wife, baby, 4yo). Even still, the forty or so guitars occupying the same room do need to be damped or it gets a bit odd sounding.
I'll probably go MDF even though I live in the (damp) mountains or NC. I don't have time for fancy these days and will probably want to build pretty cabs in a few years anyway if they work out like I hope.
It occurs to me that I might do well to first build the 4pi and play with them in terms of placement -- maybe build the 7pi later. I am extrapolating a bit from what I'm reading here but if the 4pi works in the corners of my room I might expect that the 7pi would also work, yes?
Might I please have the plans for the 4pi?
I'm hoping to get these built before classes start...not much chance after that whirlwind starts.