In short, what the support rep referenced is a common issue for all software updaters - it is impossible for an updater to know of every application and every version, and to provide update details without ever making a mistake. With that in mind, you have several options:
1.) Choose to avoid every such product because it cannot offer 100% accuracy.
2.) Choose to use such a product and ignore any inaccuracies you encounter.
3.) Choose to use such a product and report any inaccuracies you encounter.

Personally, I prefer to do the latter as it helps make the product better for both me (future updates) and other users.

Regarding a review: When looking at TechTracker, UpdateStar, et cetera, one thing I look for in a review is a comparison to other solutions available. I know they are all imperfect and that each could be equally disqualified based on their inherent limitations, so I do not find your comments helpful as I am looking for the best option that will minimize my manual efforts, not a reason to give up before I begin. However, comments that compared accuracy ratings (including percent of false positives and false negatives), the number of programs the application can identify, the ease of downloading the updates, the ability to manually override the system in cases of inaccuracies, et cetera would be very beneficial, not only to me, as a potential user, but also to those developing the products you reviewed. And that, in turn, would help them make the products better for me.

Just some thoughts from someone constantly in the market for a good updater. (And currently using/recommending UpdateStar, in case you are curious.)

John