I just read one of the post
be aware of the limit if you buy with steam
read well, lucky I didnt buy yet :D
http://www.scirra.com/forum/steam-summer-sale-and-license-question_topic71706.html
Well most of that information is for going for a company itself. For a company, you might not want steam running due the company policies or whatever.
The only real difference between Steam version and Scirra versions are:
1) Instances: Steam can only have 1 instance open
2) DRM : Steam requires initial online, and understanding on how offline mode works.
3) Profit : Due to being a retailer, Scirra sees less money from it.
For gifts, you can do the same with any steam product and keep the license in your inventory if you're not directly purchasing it for someone.
<font size="1">Beta access you can do on steam as well, although for more control on what version you use (Other than Latest Beta VS Latest stable), a Scirra license would be better met in that regard too. However many people either use Latest Beta or Latest stable anyway so that's not much of a difference
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The Steam version makes sense if you're a solo person wanting to develop unhindered. If you're a company with multiple people I recommend going through Scirra as it's easier to have a non-personal license through them (although you could make a company steam account, but only 1 computer can be logged into PC steam.)
There is some sort of sharing information deep within steam's latest client patch, but that "family share" feature hasn't even been mentioned by Steam so who knows what it is.