Guttrd - know how it feels too: Had mine swiped this time last year... I think the thieves go on a last-second spree before there's too much daylight and everybody starts sleeping with their windows open. Insurance unlikely to pay for anywhere near the value of the kit and scarcely worth trashing yor premium for it.
Here's a couple of tips (nothing quite like closing the gate after the horse has bolted), based on painful experience from myself and a couple of mates.
(1) Never EVER leave the front-face in the car (even in a locked glove-box), chances are the person gonna break into the car saw you park (and probably heard you pull up), so they'll probably be able to see you stashing it in the glove-box / boot / under a seat. If ever in any doubt abotu the area I'm parking in, I make a point of havig mine visibly in my hand as I walk off.
(2) Never EVER EVER EVER carry out your new boot-builds / speaker installs / head unit replacements directly in front of you house / where you regularly park your car unattended. Thieves could just be strolling past and see the boxes and then know if it's worth breaking into your car for. My friend got SO stung with that - the b@stards had his new shelf and boot build out about 2 hours after he put it in... and they were off down the stret before he even realised it was his alarm going off.
(3) Even bolting down amps doesn't help - grind off the bolts if necessary - no thief it gonna drill out bolts at 4am, but you can later...
(4) Stock/plain speaker covers over your top of the range speakers won't advertise the fact that you've got ?300-?500 worth of speaker in each door / >?1000 on your back shelf. Think subtle.
Any more tips? Let's try to get something constructive out of all this.