Good Article. Micosoft Word and Excel are horrible programs for desktop publishing. Converting to PDF from these programs without reflow and pagination errors when passing the file from one PC to another is tough. The only way to guarentee 100% success is to generate the PDF on the PC the document was created on.
I have been in the print on demand and publishing business with a large firm for 18 years. Anytime someone sends native files in Word or Excel, we absolutely cringe. It can be very time consuming to convert the documents and have them turn out the exact way the creator sees the documents on their end. So, I guess you could say that in the end, you get what you pay for. Free service.....I wouldn't expect miracles with Word and Excel.
I'm very happy with having pdf "printers" installed on my computers. Saves me from all the troubles and hassles on services you just listed. Plus they are more secure and flexible when concerning private data like web purchase receipts and such. Sourceforge.net has several on it that are free and easy to install. I think it would be more natural from a users point of view too.
You could always use a Mac and you can convert about anything from any program to a .pdf file. Built into OS X through the print function.
When you tell a program to print something a print box appears. You can then tell OS X to save the document to a .pdf file.
I do love my Mac.
I have to mention that from an Adobe perspective, even though the PDF spec is public and open for anyone to use, Adobe does not guarantee the stability and accurateness of PDF files created from third party applications (meaning, programs other than Adobe Acrobat). That's not a sales pitch - that's just a fact of using an open specification that any programmer can interpret and potentially mess up. So what is my point? Be very careful of the programs you use if storing stable PDF files is critical for you.