Having owned this vehicle for over a decade, I can vouch for it's reliability. The engine is remarkably strong coming up on its 14th birthday. Common problems are broken manifold studs (a $300-$400 one time repair if done right), shifter solenoid/ bushing can become tricky but easy to fix, LCD clock is unreliable, but are readily available on eBay in refurbished condition between $10-$20.
Impressively quick when you need it to be, yet always exuding class. This car is affectionately known as "4DSC" (4 Door Sports Car) and comes labelled as such from the factory on the passenger rear windows. A 91 Maxima found today in good shape is a safe bet compared to anything in its class.
At the time of this writing little can be done to improve upon it. You may wish at times it had a little more gusto when you kick down, but this can be satisfied in its identical twin 92-94 Maxima, which offers an added 30HP. However, while identical in looks, it has its own set of problems.