3.0 Si Coupe is my daily as I have no need for a second car at the moment (no kids, dogs, etc.). As much as I admire its M-powered brethren, I find the 3.0 more than adequately powered and the boot is a wee bit more practical. There's space aplenty for a weekend getaway and two golf bags fit with relative ease (without removing the clubs). And don't tell anyone, but I once brought home seven bags of mulch from the nursery. It even saw me safely through this past winter's record snows, summer run-flats and all.
That said, I do occasionally miss having a more "practical" car for chores, but it sounds like you already have that base covered.