I have a PDI-09, it sounds pretty much the same as a PDI-03 to me (just no load box). We're using the 09 and 03 to get our guitars into the computer for our in-ears live and at practice, and the 03 for demoing guitars with a Dual Recto.
It sounds good, you get a ton of presence and a lot of low end, but to me the tone always sounds flat (not 3D) if that makes sense. Thats not a descriptor I use often, but it really does fit the Palmer's sound to my ears. I've always left the tone switch at 'normal'.
It is limited to 'that palmer sound' but I think for most bedroom producers, its going to sound better than trying to mic up a 4x12 with a 57 and firewire interface. I'd recommend trying to get the PDI-03 though - then you get the option of using the Palmer sound or just using the loadbox to record a line level signal from your head and using whatever variety of impulses suits your fancy.
