I absolutely love my Sentra! I bought it with 90,000 miles and I am up to 198,000 with no problems. I have had people try to buy it from me but I refuse, I will keep it until it dies. It has been the most reliable, low maintenance car I have ever owned. I would buy another one in a heartbeat!
I had my Sentra for 5 years and would still have it if it hadn't been stolen! I had very few maintenance problems, especially considering I had it until 2002 (though my car did only have 60000 miles on it). For an economy car, it was pretty peppy, but lagged when climbing hills. It's definitely vanilla with no frills, but it's an excellent car for the money. If you're looking for reliability and good gas mileage with a great price, I would reccommend a Sentra.
When I turned 16, my father bought me my first sentra. It was bright red so I named him Clifford. I loved that car! It was great for a teen! I learned to drive stick on it. Only problem I had with that one was the clutch being 12 years old and needing replaced. Sadly, his life ended in the snow one year. To replace him though, I found the same exact car (with a few modifications) and I absolutely love her! I still will always have a special place for my first one, but they all seem to do me good. Emily (Clifford's best friend) will be around till she dies.
This is the best car I've ever owned. I purchased the car when it had only 12 mi on the odometer and now it has 163,000! It is still in top running form. I only recently had to replace the clutch after 150,000 miles. Buy a Sentra if you get the chance.