2014 Infiniti Q50
2014 Infiniti Q50 (Infiniti)

Two of the newest upscale midsize cars on the market fall short in Consumer Reports’ tests. The new 2014 Infiniti Q50 and the redesigned 2014 Lexus IS are outranked by a number of competitors, including the BMW 328i, Mercedes-Benz C250, Lincoln MKZ 2.0 EcoBoost and Volvo S60 T5.

Consumer Reports says that while the Q50 is intended to replace the Infiniti G37 sedan, the new car does not meet its expectations. “The Infiniti G has been one of Consumer Reports’ highest-rated sedans for many years, but after its 2014 redesign and transition to the new Q designation, this car seems to have lost its way,” says Jake Fisher, director of automotive testing for Consumer Reports.

The Q50 earns a “very good” overall road test score (“excellent” is the highest), but Consumer Reports finds that it still isn’t as enjoyable to drive as the G37. “Handling is mundane, due in part to dull steering,” says Consumer Reports. “The underwhelming driving experience strips the car of much of its sporty legacy. The Q50 also doesn’t ride well and isn’t particularly quiet.” Consumer Reports also finds that the Q50’s dual touch-screen displays are slow to respond, and that interior quality isn’t particularly impressive. However, the Q50 does earn praise for delivering brisk acceleration, even with the optional all-wheel drive system.

2014 Lexus IS 250
2014 Lexus IS 250 (Toyota Motor Sales)

The redesigned Lexus IS 250 earns a “good” road test score from Consumer Reports, which is “the worst road test score posted by any Lexus sedan in recent memory.” The publication tested an all-wheel drive IS 250, and notes sluggish acceleration and overall fuel economy of 21 mpg, which is 2 mpg shy of the EPA’s combined fuel economy rating. Consumer Reports says that the IS 250 falters with lackluster handling, vague steering feel, excessive road noise and a ride that isn’t comfortable or composed. A cramped cabin and the infotainment system's mouse-like controller also detract from the IS 250’s appeal.

Consumer Reports’ ratings of both vehicles have drawn criticism from some members of the press. “The 2014 Lexus IS and Infiniti Q50 are extremely well executed in terms of refinement and driving dynamics,” says Karl Brauer, senior analyst for Kelley Blue Book. “Both brands have evolved these model lines in a progressive manner by adding the latest in-car technology and crash protection, while also increasing their fuel efficiency and performance. I'm surprised by any suggestion that these cars have somehow lost their way or regressed.”

At the moment, neither the Q50 nor the IS 250 earns a “recommended” rating. Consumer Reports writes that both vehicles are too new to have reliability data, and that to earn a “recommended” rating, vehicles “must perform well in CR’s battery of tests, have average or better reliability in CR’s Annual Auto Survey and perform well in government and industry crash tests.”

Infiniti tells USA Today, “We feel strongly that once these reliability results are in, our new luxury sports sedan will be on Consumer Reports' 'recommended' list.”

A Lexus spokesperson tells CNBC, "Lexus is unclear on the cause for the low rating. We look forward to engaging in a discussion with them to get more direct feedback on their experience with the car."

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