If you go to avsim.com, you can excellent and extensive reviews on all three aircraft. Click on reviews on the top of the home page, and then aircraft reviews. There are tons, so just use the find function for each one.
If I didn't have final exams in a week, I would read all three reviews and give you my opinion. I can give you my opinion on the one of those three that id o own and have operated extensively, that being the Level-D 767.
It is easily one of the top payware aircraft in my fleet. Fantastic model, excellent systems, flies well. Overall it is also one of my favourite to operate. Now I have not tried the other two, but I have used products from each fo those companies. CLS I have used their DC-10 and A340 package (500/600). I was not impressed. These products models were decent, flying was good, but the systems were poor. The FMS was basic, and wasn't up to my advance simming levels. As for Captain Sim, I tried out their 757 and really did not like it. Not sure why, but it came down to my gut. You know, just when you don't like something. The visuals were decent, it flew nicely, but just did not like it.
So, if you ask me, I recommend based on those experiences above to go Level-D. It is touted as the best 767 to date, based on using it I can see why. But I have not flown the CLS or CS
767's. My second recommendation, read the Avsim aircraft reviews. They give screenshots, the test equipment used, and an thorough review. I read those reviews before any purchase.
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