We came across the R350 when looking at the GL450. We have two car seats but needed a 3rd row periodically when my parents are staying with us. You can only access the third row from the passenger side in the GL (and most SUV's)which is difficult for my parents. We then looked at the R350 and you can access the rear row even with car seats in the 2nd row,from both sides. The 3rd row are real seats and have very good leg room and child seat anchors if needed. The ride & handling of the car are very good. We also got the P2 package which gave us some great options, mem seats, nav, HK stereo, hands free phone(w/bluetooth) etc. After looking at 6 vehicles, we are thrilled with the R350.
Easy access, backup camera, navigation and the HK stereo which has 11 speakers, bass, Sirius, 6 disc changer and 450 watts. The hands free phone system with bluetooth module is outstanding! You can operate all of this from the steering wheel!
I would have liked to have the 500 series engine as a choice. The rear doors open very wide so be careful not to ding the car next to you. The factory DVD system is very expensive. We opted for an after market DVD player w/ wireless. (center roof mounted)- no panoramic roof. $1000 less.