EDIT:
I missed the part where this was about an Oldsmobile. So some of what I say is irrelevant, although the other info is generic and still applies.
They're not that bad or scary. Just pick the right one, and don't get carried away with dialing in more boost.
Be Realistic! Just like DoubleV says, there is more to it than just slapping it on and going. Tried to explain this to my friend who installed one on his bone stock 305, and it got very expensive quick.
You need to address fuel, and timing. As you dial in boost, you need to pull timing. There are many ways to do it. Just do a google search.
The 305 that this was installed on, is bone stock, but was rebuilt by the previous owner, so its brand new. Its in a trans am with a 700R4 and 8psi of boost. The distributor in the car is electronic, so he was unable to lock it out. He is running a Holley 650 4150 series carb, stock fuel pump, and MSD6AL2 programmable for timing with boost referencing capability.
Because of the distributor issue, I timed the car as retarded as possible (just enough the keep it running), so we could start it up and test for leaks. Unfortunately, he has been lazy about fixing the distributor issue so he has been driving it like that for 2 seasons now, and the MSD box is dialed in at 0* so it is the same as if it wasn't there.
The car runs like crap, because its more retarded than the factory setting even, and has probably less HP than it did before. However, it probably has 50% more torque, and will burn the tires at will. If he tuned it, I would bet it would be close to 260 to 300hp.
We also had a few other challenges along the way, like brackets, thermostat housing clearance, and pulley alignment for which we had to machine a spacer for.
You may run into other challenges with clearance too, like fans, brake booster, Valve covers, AC, etc etc... Its not a walk in the park. But its not that bad either.
Im not worried about this engine living for a long time if he just tunes it correctly. Although he is probably doing some decent damage to it right now running it the way he is. The 700R4 is not doing so well. It was also brand new, and now it feels like its on its last legs.