The OP in this thread motivated me to put my stock airbox back on, too.
This was no small thing for me, as I'm an all-thumbs sort of under-the-hood mechanic. (For example: when I was done, the car wouldn't start, providing me with my week's worth of adrenalin all at once. I figured out pretty quickly that I needed to reconnect the battery, but it was panic city there for a minute.)
All-in-all, it was much easier than I thought it would be, and that Giant Sucking Sound is, of course, blessedly gone. There's still the Boxer grumble, considerably more enhanced than in my wife's Outback XT; and that's just fine.
I can't speak to the torque thing, as I didn't drive it enough to get a real feel. But there are no weird lights showing, and it sounds happy. Thanks to Mike for the suggestion!
Now I'll have to resist the siren call of the AccessPort... HPH
PS: If anyone wants a slightly used SPT intake (from an 08 LGT.B, about 3K miles of "used"), pipe up. It's got the heat shield, too.