Depth is good. I would order a pair. My suggestion is start wtih back doors. If you think about it those speakers are closer to your head then the front mounts so you will hear the difference right away if adjusting the fader slightly to the rear.
2013 S4 Loaded (and NO RFT's) Awesome is an understatement
2008 MT X3
RIP you were a faithful sidekick and will be missed.
2007 AT X3 RIPOS
2000 Jeep Cherokee
1997 Twin Turbo RX-7
1984 GTI Wolfsburg Edition Neuspeed and more