In my opinion, the best Nissan Maxima upgrade alarm is the Cobra AK4615 CAN-BUS upgrade alarm made by Vodafone Automotive. It works flawlessly with the factory remote.
The Nissan Maxima already has a factory fitted immobiliser and keyless entry so has a reasonable level of security as standard.
The Cobra is the only CAN-BUS alarm I recommend for most Nissan models, that said it’s also possible to make any OEM upgrade alarm work with this car.
If you don’t have the Nissan Remote then a Remote Upgrade alarm is also possible, as is a new keyless entry system.

Nissan Maxima (A34) 2004-2008
Why do I list the Maxima when others don’t?
It’s quite common for me to come across vehicles that are not listed on the Vodafone Automotive website. The Nissan Maxima is one of these, so I have to test the vehicle myself, take notes and make sure the software is going to work.
Once I’m happy I add the car to my list of Compatible cars.
Cobra Alarm Installation Details
Below are some photos of how the alarm looks when installed:

Ultrasonic Sensors in the Maxima

Cobra LED over-ride switch in the Nissan Maxima

Alarm works with the factory Nissan Remote or a Cobra Remote Control
Also works with the (A35) Nissan Maxima 2009-2014

Nissan Maxima (A35) 2009-2014