Just curious but how many here can claim their SVX to be running top-notch, as in liquid smooth with the engine humming so peacefully you can barely notice it's running? (and if so at what mileage?)
I'm not sure if it's because it's a boxer (as I have no other SVX alongside to make a comparison on) or because I most likely have some more coil packs that are losing out but I hopped back into the impreza for a spin and I just want my SVX to run that smooth at idle. (and that thing has 190k on it!) Or better, can it or should it?
Has anyone here ever replaced every single coil pack and can say for certain it made a huge difference or not? I'm about to plunk roughly $600 in much needed new tires
and I can't get the idea out of my mind in wanting to go ahead and replace the other 5 coil packs in hopes that everything will run smoother. Of course, that comes at a cost of
only 
$400 ...but given the fact that nothing looked wrong at all with the coil pack I replaced, I can only suspect the others could just be worn enough in needing replaced. It is, afterall... 168k on the same coil packs. It does have a new set of NGKs however.
Is there a general rule of thumb for life expectancy for coil packs anyways?
I'm going to go ahead and replace my gas cap, fuel filter and pcv valve to see if that makes any noticeable difference at all but I'm betting it's completely unrelated and will have no positive effect.