Are you pretty low on gas when that happens? It could be fuel starvation.
Um, Nissan doesn't even make the battery. They just buy it off the shelf of a supermarket just like you do. It's not their fault whether the battery dies prematurely or not. Batteries run out of power and die, that's a fact of life. Something to do with that pesky law of conservation of energy or something. It's only a few bucks anyway. The battery in my remote lasted over 2.5 years and still had juice when my car was totalled in an accident. Maybe yours was a bad batch of batteries or something. Not Nissan's fault. And definitely nothing to make a fuss about. Again, wear and tear item. A floor mat is nothing more than a cheap rag to protect the underlying carpet. Yes, they wear out over time. No big deal. Throw it out and get another one. They're pretty cheap. And be grateful you even got a floor mat. Porsche would charge you twice the Z's price for a Cayman S and floor mats are still an extra cost option. Wear and tear items. There is no predicted life expectancy for them. Either way, these are just minor things that cost peanuts. Seriously, you make it seem like the sky is falling just cuz your floor mat is a bit worn out or your keyfob battery needs replacement
They're probably wrong. The problem seems to be caused by the fuel sending units in the gas tank and not the fuel gauge in the dash. Crappy dealers are everywhere. Doesn't mean Nissan is a bad company or the Z is a bad car.
I'm not sure what you're doing, but it's supposed to click once if you move it all the way up so that it locks into place, and if you push it down it clicks once as it unlocks and falls down again. If it's clicking or squeaking more than once, or if it doesn't stay up by itself maybe it needs replacing.
Sounds like you got an excellent car for your money. Go pay 2-3 times the money on a porsche, watch as your engine self destructs due to known engineering defects, and if you're out of warranty watch as Porsche gives you the proverbial middle finger as you're on the hook for the cost of an engine replacement.
Seriously, your tone makes it seem like the engine blew up, the gearbox seized, the wheel fell off on the highway, the brakes failed, the diff self destructed, the frame cracked, and the body rusted right through itself. Yet all your problems are a dead keyfob battery, a worn out floor mat, a slightly inaccurate fuel gauge, and possibly a squeaking seatbelt arm. Hardly anything to lose sleep over it.