Honestly, I don't like Harris in this application. I think I've said it before, but I think he works well on his own, but comes across as a bit rude and uncomfortable a lot of the time. LeBlanc is okay, when he is genuine I think he's actually really good... but sadly most of the time he's still delivering the lines the way he has done for the last 20 years. Reid is annoying, likable at the same time oddly. I think chemistry will come, but it's got to develop naturally - if the producers and writers try and force the guys into playing specific characters (i.e. Clarkson, May and the short one) then I think it might be unwatchable.
Some of the format changes, moving to a sportier car for the celebs, breaking down the celeb bit to smaller chunks I like. But, I can't shake the idea that whilst the format of the show remains so similar to the Clarkson years, comparisons will be made and new TG is always likely to struggle because of how good it was 6-10 years ago.
As for the actual content of this first episode, Harris doing what Harris does in the FXX-K was good. Given the scale of the Kazakhstan road trip, it didn't feel particularly epic, but it was okay.. to be honest, at this stage... not being painful to watch puts it ahead of the competition, though I still look forward to the days when we start to see something as good as we had in the late '00's.