I use Quickbooks, in comparison to sage its a doddle, anyway more by pm
Just don't fall into the trap of thinking Sage's own backup routine backs up *everything*
If you have custom templates, it doesn't.
Damn, how geeky was that for a first post!
Sage gives you a tickbox list of what you want to back up, templates is one of the options, most people admittedly only back up the data file.
A product called Cookedbooks comes with many recommendations including Ken Dodd.
All these software packages are off-the-shelf. The best one for your requirements depends on your business and its accounting needs. Some are better for manufacturing companies, others for service companies etc. A bespoke system may be required for unusual trades. XL spreadsheets are great for medium to small businesses. You can have P@L and B/S pages at the front which are linked to all the various ledgers. Analysis of the ledgers will be sub-sheets aswell. It all double entry but you also understand the accounts better.