Vehicles & Customs

We drive down every year, and have for 30+ years.
Get your vehicle permit on line. No extra cost, easier. Then, when you get to the border, you get your FMM (visa) When you fly home, you will surrender your FMM at the airport, and get a new one on the way back, included in the price of your ticket. Return your vehicle permit before 180 days at the border. They come out, remove the sticker, and you will be credited for your deposit in a day or maybe two. You do NOT need to turn in your FMM. As aduana says, "It expires."
Very straightforward, very easy.

Certainly sounds easy. I assume you've actually done it, recently?
What is the advantage (other than, perhaps, convenience) of obtaining the Temporary Import Permit (TIP) on-line? In the situation we're discussing, are you more likely to get your vehicle deposit returned because you purchased it on-line, rather than simply at the border on entry?
I've heard that there is a now a link between the registration number of an FMM tourist card, and the registration number of the TIP. Turn-in your FMM and the computer rings a little bell saying "Where's your car?" One foreigner who had to fly home during his 180 day tourist card period reports being tracked down at the airport just as his flight out of Mexico was to leave, and required to immediately pay a 390 peso fine for leaving the country without his vehicle. If that was the worst that could happen, I'd go for it. The story didn't provide any details of what happened months later, when he returned to the border with his vehicle....did he get his deposit back? Was he banned from ever bringing another vehicle into Mexico? Etc., etc. Or maybe he's in a Mexican slammer and hasn't been heard from since?

PS: We've driven down many times, so are totally familiar with the "normal" procedures. We've always paid our deposit in cash, and have never had any problem getting the deposit back when we've exited the country.