HobokenViper,
That's incredibly helpful, thank you very much for chiming in! I am very familiar with your nice 3-page thread on battery woes, just never realized you were in the exact same situation as me. Except that my car has never failed to start on a first try, just started getting progressively more sluggish.
Just got back from the garage for a quick check of my oil - it looks crystal clear (at least on the dipstick) and is full, so hopefully no mechanical harm done by my prior winter "wake up" drives. Paid close attention to every single one of the exotics in the garage, couple of Phantoms, a Drophead, a few Murci's, couple of Gallardos, Porsches, Lotuses, a fellow Viper - none have battery tenders hooked up. It's either that they are all in some sort of safe/sleep mode (other than my friend's Viper which seems to be holding well in full alarm mode), or the garage is actually heated enough that temperature drain is not a problem, and for some reason my car's battery is probably singing it's last song (sulfation, age, etc.).
Either way, I don't want to drive the car this winter season any more and your suggestions all make sense, except for a point made in a post I read somewhere that windows need to be lowered in safe mode (can't recall the reason cited). I'll try to find that reference. If true, I'm not sure I'll have enough peace of mind knowing that my car's sitting in a publicly accessible garage a quarter mile away from me with a disabled alarm and windows cracked open.
But thanks again for an extremely helpful and informative post. I think I'll end up heeding your advice pending some more research into the window issue.
I had posted a similar thread not even 1.5 months ago as I too live in the urban town of Hoboken just across the Hudson River from New York City and keep my cars in my building's parking garage. There are a lot of exotics in my garage as well (including a silver Mercedes McLaren SLR parked next to my car that never moves) and there isn't a single power outlet available to use. I was scratching my head as to how the hell people do it, and I came on here and got some great advice that has since saved my car battery:
1. Put your car in the battery save mode. While it will disable the car alarm, the car also remains locked and the battery is effectively cut off from all the car's systems as if you hit a cut off swith to the car's power entirely, and unless a car thief has your car's key and can figure out where the key hole is hidden under the door and also can figure out how to shut off the battery save feature with the key, your car is probably safer sitting like that than if it had the alarm set. Do this!!!
2. Buy a new Die Hard Platinum 34 Series battery for the car. I replaced the battery in my 2008 as it was seemingly starting to go bad and was losing cranking power in just 2 weeks. The new battery is powerful and awesome!
3. Buy a Die Hard Platinum battery backup power supply and car jumpstarter. You will never worry again if your car is dead as this thing works like a charm, but if you follow steps 1 and 2 above, you should never have to use this amazing invention unless you need a backup power source for a couple days if you have a major power outage.
4. Dont drive the car in the winter like you have been. I don't think it is good for the car, and you are probably discharging the battery more than you are charging it every time you fire her up and drive loops around your parking garage. Your neighbors will stop thinking you are a crazy person too wen you stop doing this. Haha! Funny, I had the same thought before I learned about steps 1 & 2, but it never got to the point of doing laps around the garage for me thankfully.
The solutions are really simple, and the battery save feature will hold your battery's charge for 3 or 4 months if not longer, especially if your garage is kept decently warm. Hope this was helpful!