The Saab clutch is tough, but there are a couple of things you need to be aware of.  First, it can become unpleasant long before it quits working.  And second, the nature of turbocharged cars tends to invite abuse for two reasons.

Typically, a clutch will do its job until it just wears so much that it can no longer move the car without clutch slippage.  There are other considerations though.  For one thing, the release bearing can become noisy, in which case it will squall when the clutch is released.  It might go forever before it fails completely, but the noise is irritating.  This is what prompted me to eventually replace the clutch in my '91.  For another thing, hot spots and wear build up on the faces of the pressure plate and flywheel, and they can cause "chatter" or "judder" when the clutch is released.  It can be very irritating.  If the rear main oil seal leaks and oil gets on the clutch disc, chatter can get unbearable.  Another thing that can happen is the slave cylinder (down in the bowels of the clutch works) can fail - or leak oil onto the disc - or get sticky and cause uneven release action.

Now for the second part, the nature of the beast: First, the turbo Saab is a high performance car, and people tend to demand a lot from them and drive them hard.  What makes matters much worse is that it's just a low-compression, small 4 cylinder engine until you get the turbo going.  Therefore, in order to get the car to move its ass initially, you have to rev the engine and slip the clutch.  Once the turbo kicks in, enormous amounts of power are transferred to the clutch - which is already slipping, because that's what it takes to get the power going.  So it's a regenerative thing: You rev the engine and slip the clutch to get into the turbo power, then the turbo power kicks in and blasts into the slipping clutch.  For that combination of reasons, the clutches of turbocharged cars lead a very hard life.  The hard life is manifested soonest as hot spots on the steel surfaces, and the clutch can become unpleasantly rough and choppy when it's only half worn out. 

A Saab turbo clutch could probably last a quarter of a million miles pretty easily, if it was used gently.  Or it could easily be shot at somewhere around 100K miles if driven very hard all the time.  On average, it's absolutely unreasonable to expect more than 150K miles from a turbo clutch.  So keep that in mind when you're looking at a car with over 100 K miles on it - you're almost certainly looking at a clutch job while you own that car.  For Aeros, it's that much more of a problem - more power, higher final drive ratio, higher expectations from the driver, probably more abuse.  Figure 125K miles is about average clutch life for a turbo car.

The real test is smoothness.  If the clutch operates smoothly and positively, then it's in good shape.  You should try a couple of  spirited starts, slipping the clutch, to see how it does.  If it chatters a lot, then you know what you have to live with, at least.  If it operates smoothly and quietly, without slipping, then it's probably in good shape.

If you do the clutch yourself, you should do it all: Resurface the flywheel, new pressure plate, new clutch disc, new release bearing, new slave cylinder, new master cylinder.  As for the rear main seal, that's a tough decision ... I couldn't get one installed properly.  In general, I say leave it alone if it isn't leaking.