I have a 2016 LT e-assist 5.3 wth 8 speed transmission. 13000 miles and no complaints except for the bolt falling out of the brake caliper bracket on the front right wheel, damaging the rim. All remedied under warranty.
I installed the GM version of the rear underseat storage compartment last night. Fit perfectly and operates as designed. Although a little pricey.
https://www.amazon.com/Accessories-23183674-Underseat-Storage-Compartment/dp/B0199WFB3A
I'm not sure if the "hybrid" battery placement changed for the 2017 models. If I remember correctly, mine is located under the center seating position of the front seat. If GM did relocate it under the rear seat, that would present a challenge with storage options.