Is almost all poker software advertised on the net a scam?

[Hagbard23]

There are a couple of programs that repeatedly get recommended here.
These are obviously tested and approved (pt etc.)

But what about all the software, you can get for free, when depositing a certain amount of money? Makes me kind of suspicious. They all advertise with great features (instant pot odds etc.) and get great reviews on many poker sites (paid by the software-companies?).

I think of software like: poker office, texas calculatem, poker sherlock, calculatem pro, holdem genius,
poker indicator, poker pal, poker spy.

Yet nobody here on 2+2 mentions these programs or seems to use them.
Because they all suck? Because they all are spyware/trojan-infested etc.?
or what? Or are they just useless for a reasonably good player?

Please tell me what you think? Are any of the mentioned programs any good?
I mean, if there were no strings attached, a feature like instant pot odds calculation could be very handy.

(PS: and something different: where can you download the dollar-tobb tool? Browsed its thread, couldn't see where)