I really like the OEM Kicker speaker upgrade package. I had the dealer throw them into the deal (freebies) at purchase. Installed myself on day 2 of ownership.
These in concert with the Helix PP50DSP
amp are a fantastic, stealthy upgrade.
As for the sub, I agree. I wish Subaru would have made an underseat unit. The Kicker 10" unit for the back takes up way too much space. We need to work an older unit into the new mix!