I love Office2 HD. I've had it for over a year and have seen regular upgrades, great support and can recommend it highly (as I have to friends). I love its integration with Dropbox but would like syncing for doc and xls changes. They tell me this is planned so then it will be everything I need. I also have Pages but did not buy Numbers as there is no organization, no Dropbox integration. I looked at a number of others in the beginning and since. There are some other very good ones but I haven't found a reason to switch, so I can only tell you that it functions very well for me. Adding Goodreader with it makes a great production duo.
Diane B