Clutchs depend on both how it was installed (was the flywheel resurfaced is the main player and if it was PROPERLY broken in), and ofcourse the driver...
To test for this:
Put on the ebrake.
Start the car with the clutch in.
Put it in 4th gear.
Slowly let up while pressing the gas.
If the car doesnt stall, then its probably the clutch...
You can diagnose most of the other problems with a Helms and a volt meter...