Well I'm kind of a socioeconomic snob/purist when it comes to owning exotic cars. Personally I'd only buy one if I could afford one brand new and paid for out of pocket which would take about $25M+ assets (preferably liquid net worth) to comfortably do.
I mean owning a used $90k gallardo looks nice at first glance but expect a lot of problems if you intend on driving it 10k or 15k+ miles a year (or more).
And actually that brings me to another point, I would feel silly spending $90k for a used lamborghini and then only driving it like 3-5K miles/year. If I bought an exotic car, I'd certainly take care of it but I'd also drive it (mostly) like a daily driver, but then again I don't really "get" this "beater car/daily driver vs weekend car" thing that a lot of people do.
From what I've heard, these used Gallardos are just a ticking time bomb waiting to explode with respect to being a maintenance nightmare. If you're willing to take that risk, then go for it. If you're planning on mitigating that risk by barely driving the car, then I say what's the point? Sure, it's a huge attention grabber, but
1) Personally I'd feel sheepish driving a used lamborghini knowing that people are looking at me thinking I paid $200k+ for the car 7 or 8 years ago (but to each his own)
2) I wonder if it's really a good value @ $90k regardless of how you intend to drive it. If you drive it a "healthy" amount, then you have to worry about reliability issues, at which point you'll wonder you would've been better off buying a brand new porsche 911 or something.