PDF's look nice,however its much easier to get data into a pdf than out of one. I avoid anything that used a back end database like that because what happenes when in a couple years you want to update your document, you can't esaily edit a pdf, if you copy the text out you loose all the formatting, etc.
With any software the cost is not what you pay for it up front, the total cost of ownership is what it costs to support during its life. Years later you may be forced to hand type data from a printed pdf if you use software like that. if you stick with something more open from the start then you can simply open the file and edit it in afew years.
I'm worked with computers and in IT a lot and have seena lot of poeple get stuck with data in some format and waste a lot of time re-entering data because of using programs like that.
There are a couple somewhat recent threads on this form where there are links to templates you can use which do not require special software or a propritary database format.