I think it has to be. The 900/5 has a bit of a reputation for underperforming relative to expectation... Not that it doesn't meet spec, I don't know, but it may not exceed spec by as much. To jam 900 watts and 5 channels into the same form factor, SOMETHING had to give...
Musicar Certified audio upgrades
OE-Look Enclosures for F10/F30/F32/F22/etc
Add-A-Sub and Full-Bass Packages
Full Cabin 3W and 4W Upgrades
F10 Level Three Add-A-Sub