They aren't very durable. The plastics in the cooling system have to be replaced every 100K miles or so. If any air at all gets into the cooling system the heater doesn't work but the car will overheat. The coil on plug setup is so delicate that the first step to change a tire is to replace the COPs. The plugs have to be replaced at the same time, and if one coil fails they all have to be replaced. If the coils are marginal long enough, the RFI feedback will kill the computer.
Now, I'm going to stir up the car's cheerleaders. This stuff always gets them wound up, but as a new owner you need to know. The engineering is also a mess on this car too, as they decided to go at a lot of things in new ways. Instead of running coolant into a radiator like almost every other car in history since they started putting coolant-based heaters in them, and using a door inside the heater box to control the heat, they put some complicated valving structure in known as the DCCV. On the Gen 1s (your model) they decided to control the alternator with the PCM rather than by using a regulator like every other alternator in the world. What this means is you can only use a Motorcraft alternator, and you can't really add much in the way of powered accessories to the car. In other cars, if you add a high powered stereo system, then add a high power alternator to power it, no problem. On the LS, if the computer decides that the alternator only needs to produce 38 amps, 38 amps is all it will produce even if the draw on the system is 100 amps, and there is no way to alter this. The alternator's power production acts like it is controlled by a PCM table that decides what the power draw should be for a given situation instead of by measuring what the actual draw is. They at least wised up quickly to this one as they dropped this control disaster on the Gen 2s. Then there's putting the fuel filter behind the left front wheel well liner where it's hard to get at but poorly protected against road debris. Hit something hard enough to penetrate the tire and keep going (like a broken leaf spring from a tractor trailer) will punch right through the wheel well liner and into the fuel filter. Then there's the way that if the seal on the back of the hood is missing, water will dump into the COPs and short them out every time it rains.
None of this includes the fact that the car has been out of production long enough that the dealer is no longer making parts for the car, and since the car was low volume this means that some parts are becoming impossible to find new anymore. What makes this worse is a lot of the car is designed to last 100K miles, then replaced. If you want to see the future, go look at a message board for the Buick Reatta.
Not all bad though, for example the brakes only take about 30 minutes per wheel to do, and if you have a bad bearing replacing them only adds about 30 minutes to the job. It would only add 10 minutes to the job because all it is once the brakes are out of the way is three bolts and one wiring plug, except they decided to hide the ABS sensor wire plug behind the wheel well cover, and this is a pain to get out of the way. The entire bearing assembly is a hundred bucks to a side, and you get new lug bolts, a new ABS sensor and new wheel bearings in the package. And they apparently put a little hatch in the floor under the rear seat so you can get at the fuel pump easily.
I don't mind telling you that I wish I'd have researched the LS a bit more before buying, if I had I'd never have bought one.
