I still have my 2017 Optima hybrid and I feel it is quieter inside than the Stinger. That though, could be attributed to noisier tires on the Stinger however, our US market Optima SX-L and Hybrid EX are top of the line for their respective class but to get some of the SX-L goodies, you would have to get the Plug-in hybrid. Things like the 360 camera and nappa leather weren't offered on the Hybrid EX. I think the Stinger in Korea got the luxury car treatment but not for the US. I don't believe all our windows are laminated, just the front ones, we don't have 1 touch up/down window switches on the rear windows and I feel the sound insulation is less as well.
I first drove an Optima EX with the 2.4L engine in 2016 when the were first released, the quiet cabin, supple ride quality and clean sounding audio system made it feel like you were driving a luxury car. We ended up going with a Volvo S60 T-5 R Design which wasn't as quiet but I got a great lease deal on it, when the KIA dealers weren't wiling to play ball on their new, at the time, SX-L's. A test drive of the 2017 hybrid had me trading it 2014 to get the upgrade. While I wanted a 2.0T Stinger, it had more cabin noise than the Optima and I wasn't going to do that. I did test an A5 2.0T Premium and the noise was a little better than the Stinger 2.0T and closer to the Hybrid however, the
3.3T Stinger beat it in price and options.
Will I get another Optima? Probably. Would I give up the Stinger for it? That's something I will have to look into later. I saw a video from a Korean presenter that mentioned the AWD version might have an electric motor driving the back wheels. That to me says plug-in hybrid and if it made as a Sport hybrid. I would be down for that and trade the Optima hybrid. If they do something similar with the
Sorento, I would take the Optima and trade the Stinger so the wife could have her hybrid SUV.