The best thing about the software is the ability to do 'what if' analysis to see how different investments will affect your tax bill or tax rebate. Also, when preparing a whole family's returns, the software can also determine which spouse should claim certain deductions to maximize the tax benefits. Beware that online software may allow you to save different 'what if' versions of the return. For a few more dollars, buy the CD.
I use the taxtips.ca tool (here) for rough calculations of taxes. The site offers a basic calculator for an individual and a detailed one for you and your spouse where you can also account for more deductions and credits. The taxtips.ca tools allow you to predict next years' taxes while using last years tax software to predict next years returns may only be an approximation (as tax rates change). This is not the case for 2012 and 2013 where tax rates are steady.
Ufile software has been a mainstay in our house for over 5 years and has always worked without a glitch. We have tested its features for the usual options including business expenses and earnings, and for exotic flow through limited partnership resource pools. Support has been outstanding, especially on those flow through shares, where it was greatly needed. Ufile is usually available for about $20 - this year I picked it up at The Source. This year there are 'free' CDs mailed to existing customers that you can pay to activate - that is convenient! You can file up to 10 returns, and your 'what if' scenario versions don't count toward the total (it only counts when you finalize a return to NETFILE it).