Phillip Helbig writes:

> There are a lot of very good cathedral products out there which are
> very good and chugging away and are very successful but one never
> hears anything about them.

I do not doubt this point.  In fact, there is one, a computer
algebra system, that I use.

That said, all other things being equal, I find it easier to trust
an item if (1) it is of modular design, (2) it is platform and OS
independent, and (3) I know that the source is available for free.

I regard each of these characteristics as something that promotes
its long term reliability for me.

[The computer algebra system to which I alluded is reasonable for (1)
and (2) and not completely terrible in regard to (3) if one knows the
ropes although, to my knowledge, the source is not freely available.
(I think that the source is available for inspection at a price, but I
would never go there.)]

I have seen many, many proprietary things lacking these
characteristics that have failed me and others at critical moments.

(And I have never understood whether "bugs" are covered by copyrights
and, if applicable, patents.  ;-) )

                                   -- Bill