The first TLX replaces both the TL and TSX, offering either the 2.4 with an 8-speed dual-clutch or the 3.5 V6 with a 9-speed automatic, plus P-AWS or SH-AWD depending on version. That makes it a more varied car than it first appears, and the used-car logic changes a lot depending on which drivetrain sits under the badge.
The 2.4 DCT needs good software and smooth low-speed behavior, while the V6 car must prove that its 9-speed and, if fitted, SH-AWD were serviced properly. A good TLX I feels modern enough and mechanically coherent. A poor one feels expensive before any repair bill even arrives.