Back in 2008, I bought a new head unit, amp, cross overs, component speakers for the doors and new speakers for the dash. My 2003 Boxster came with the crappiest stereo ever made, with only the dash speakers. I didn't care which stereo it came with because all the factory units pretty much suck and I knew I'd end up replacing whatever stereo it came with, so for me the low end stereo option didn't matter. I couldn't be happier with the sound. Came out great. Doesn't look stock, but I don't care about that, as long as it sounds good at any speed.
I didn't do the install myself, as it came with the equipment for no extra charge. I did add some dynamat behind the speakers, on the door card and the door metal skin to keep the doors from rattling and improve the sound. To me, upgrading the stereo was totally worth doing.
This is how the installer ran the wires into the doors:
