The 'rumble' is not too noticeable when starting off if you give a moderate press on the accelerator so that the ICE starts right away. If you start off with a lighter press on the accelerator so that you are in EV mode - then there is a slight rumble when the the ICE does start. Sort of like the sound of the main engine on a ship starting up several decks below. I don't mind it as it makes you more aware of what mode you are in. I don't think passengers are aware of this and it is more noticeable to the driver.

There is also occasionally a slight 'lurch' that feels something like a torque converter locking up. However since there is no torque converter, I believe it likely comes from the PSD (Power Split Device) - possibly when some major event such as the MG1 rotor changing direction occurs.

My biggest frustration (see posting on 'Remote Start' of 30 Sep 2007) is that I can't get a remote starter for it and there is precious little information available about remote starts for hybrids. One unit (XK07 from 'www.bypaskit.com') states that it is for the 2007 Altima with push button start however it makes no mention of whther it is suitable for the hybrid model. Also when I compared their (bypasskit.com) XK07 wiring diagram for the BCM (Body Control Module) bypass module hookup, I see differences between their wiring diagram and that in the 2007 Nissan Altima Hybrid Service Manuals. In the area where I live, (Ottawa Ontario) I don't believe anyone else has done a remote start installation on a NAH and I am very leary of being the first.

Bottom line though, I love the car and highly recommend it.