I have used Thesaurus for the last six or seven years and have found it to be very user friendly. Would never consider changing from it.
One great advantage, I find, is that you can copy any of the reports into Excel write easily and add columns and rows and play around with the figures.
Also, as far as I know, you can download it and use it for free for three or four weeks, then you pay around €150.00 and they send a code to let you continue using it.
I don't have any experience of Payback, so I can't comment on it. Hope this helps.
Nolo77.