About Hikashop and a question about registration

I have two wonders:

First of all, I've been looking for information about Hikashop in a less than normal sense. Before purchasing a commercial version, I am looking for documentation explaining information such as, where did Hikashop come from? How did Hikashop come to be? What is the size of its maintenance and dev team by aproximation of small, medium, large, etc- How active is the development of Hikashop? If I purchase hikashop, what is the likeliness that hikashop will remain to be around in 5 years? What is the likelyhood of Hikashop supporting my version within the next year? How old is Hikashop, and how long has it been stable?

If I can be pointed to such documentation, that would be nice, but I still welcome an exmplanation if not.

My seccond question is- How can I make it so that a warning is shown if someone attempts to register an account that already exists? currently the page just refreshes.

HikaShop was developed from scratch more than 3 years ago by myself.
I started the project because I was frustrated with VirtueMart which I had used before.
We are 5 people at the moment for dev and support.
The development is very active. You can look at our changelog: www.hikashop.com/en/support/56-hikashop-changelog.html
We will still be there in 5 years. There are tens of thousands of shops out there made with HikaShop.
We do not support old versions. We provide an easy system to update HikaShop and we try as much as possible to be backward compatible so we expect our users to update HikaShop like they update other extensions and joomla itself on their website.
HikaShop has been released for a bit more than 2 years and has been stable for the same period.

There already is such a warning (it's actually joomla which generates and displays it, not HikaShop). If you don't see it, it is because of your template:
www.hikashop.com/en/support/61-hikashop-...issues.html#messages

Wow, Thank you for such a detailed response. This really helps.The only other thing that leaves us hanging from the thread between purchasing and re-discussing in our business is the guest (no registration) option included in the commercial versions. Is it included in all commercial versions? As in, will that be included in Essentials. It's not on the list at all for features (since it's sort of a small feature anyhow I assume).

The "Checkout without registration" feature is listed for HikaShop Essential here :
www.hikashop.com/en/hikashop/essential.html
So yes.

Oh, I didn't see that, thanks once again!