I don't think that you can go wrong with any year of NX but that's just me.
According to Consumer Reports
Road Test:
The Lexus recipe for success: Hide the Toyota mass-market roots under the Lexus logo by filling a car with amenities and luxury trappings, a more supple ride, and a quiet, soothing cabin. Even a pro can't sniff out the Camry beneath an ES sedan. But with the new, compact NX, the souffle falls. The car doesn't coddle you like the wildly successful Lexus RX -- the midsized crossover vehicle that started the whole craze. Nor does it thrill you with BMW-like handling. It just feels like an upmarket Toyota RAV4.
Highs
xLexus' reputation of reliability
xThe NX 300h hybrid gets excellent fuel economy
xRelatively agile -- handles better than the traditional Lexus
Lows
xLousy visibility, especially to the rear and sides
xAnnoying touchpad infotainment/navigation system contro
xSnug driving position
xTight cargo space
xHybrid version is rather expensive, plus feels and sounds underpowered
Reliability 87/100
Customer Satisfaction 3/5