It might be inaccurate - but it is officially licensed. So that's good enough for me. Personally, I think this looks a lot more like Ecto 1 than any of the incarnations in the IDW comic books. (yes I know there's an issue with the caddy trademark, etc, I'm just pointing it out).
Plus, I think as Troy pointed out in one of his private sector columns, the only reason we can point out all the inaccuracies now are because of the DVD/Blu-Ray/High Def modes that we can now pour over to our geeky heart's content. Before that, VHS transfers wouldn't have provided near the detail to work off of. (Case in point - how far we've come with making “screen accurate” proton pack props. Also each is slightly different from one another anyway).
Either way, to each his own. I plan to pick up several of these. If it's not your thing, that's fine too. I can see why people would want to save for the Mattel Figures or possibly a mini-mates Ecto down the line.
I will say I'm glad they didn't plaster the whole side of the car with letter of “Ghostbusters” or “Ecto 1” the way that they messed up KITT when Matchbox released it. (I don't remember if it said “Knight Rider” or “Knight 2000” but one of those was plastered in red letters long the side of KITT. Sure that's the way the original toy line was released, but I don't know why they put it on a new, totally separete release of the car.)
Also, I'm looking forward to this because of the justice Hot Wheels did to the Back to the Future DeLorean. It was originally released by Johnny Lightening (same group that did the Ecto 1A back in 1997). The JL delorean was nice but wasn't exceptionally accurate. Hot Wheels later re-released it (all 3 different movie versions - though I only have the first) in a character wheels Japan series. It was absolutely gorgeous. That Japanese series also saw a re-release of KITT and KARR which was far superior to the Matchbox version. Granted this is a “main line” car so it probably won't be as detailed as those Chara-Wheel releases, but I'll bet it's going to look pretty darn good.
Just my 2 cents that nobody asked for.