BTW, since I posted the link to Christian Buil's (old) article, let me clarify in more detail why I did it:
Firstly, it was because (as someone pointed out earlier) only this kind of comparisons, with enough support of facts and images and measurement data), are really useful.
Also, the models he was comparing they are still around (second hand), and for people with tighter budgets (and some people on this forum tend to forget the fact that the majority of prospective astro-photographers belong to this category) they are still a viable option.
Finally, I deeply respect the work of people like Christian, who share their knowledge, experience and expertise with the rest of us without thinking about their own material benefit.
In my opinion it is a good thing to keep an eye on such websites, there are always updates, and, by visiting them perhaps they will let be known that we appreciate their work
