Whatever the engine that is used in these games doesn't matter much to me. Its the quality and effort put into the game, as well as if the story is at least decent. This has an intriguing twist to the "Back to the future" story, has good models and sets used, and great animation quality. Is it the best Ive ever seen? No, but it definitely ranks up there. Ive seen games that use DAZ, HS1 & 2 that look like trash, and ones that look amazing. Quality takes time, practice, and a good rendering GPU. I don't know what the GPU used to render this is, but if it were lower end it could add to how long the releases are for how long it takes to render it. Not to mention any scene edits or re-renders if something didnt fit the scene once added in.
Speaking of the story, With the talk of paradoxes and the fact that MC cant keep it in his pants and not disrupt the past, I get the feeling that Hes gonna not only be the father of most of the teens in the future(Krystal,The twins,Darci, Skylar, the runaway cousin/daughter of jenny, etc) but possibly even be his own father, and possibly be the Masked man in black. And now with the way chapter 6 ended and the allusion to someone always talking about training, parkour, katanas and such, we have a possible lead on who the ninja is as well. In the words of the Doctor, its "A big ball of wibbly wobbly, timey wimey stuff"
I kinda hope theres a twist that makes me mostly wrong, but either way, I like it.