It is inevitably complex because what it does is complex but matters are well explained in videos which if followed logically will explain most standard uses.
There are a number of micro-integrations with other products and it seems very customisable.
That the products has had some stinkingly awful reviews seems to reflect more on the competence (lack of) of the people dishing the ordure than any defect in the product which is robust and - when you learn your way around - is logical and remarkably user friendly. There are tool tips for everything and the back office layout is remarkably logical and well thought out.
I have noticed that many complaints seem to be based on the fact they charge a subscription or for on-server support. I never quite "get" why people expect a product to be "given away" or for a developer not to be paid for developing it. Furthermore this component enables your website to take money so it seems entirely reasonable to me that you should pay for it.
I have posted two questions through the forums and both have been answered quickly and competently by people working with the developer at no charge.
I have only upgraded to the latest version on my staging server but there appears to be better written documentation for it and my test upgrade was painless and the data preserved.
I am a refugee from Community Builder which people always tell me is open source and hence better meets the spirit of the "Joomla Community". Well you won't get far with Community Builder without you shell out for the manual (fair enough in my opinion) and the optional CBSubs for my site was 295 euros for the product.
This product works well with JomSocial and has the added advantage that you can style up your pages to match your site relatively easily so there is no need for your site to look like you built it in the mid 90's.
There is a slightly steeper learning curve than with JoomlaPack because the product requests you think a little more about security but the support you need is inbuilt into the installation with links to simple explanations as to what you need to do (and why you need to do it).
If you need support there is an excellent free forum which is monitored by the developer who is rightly proud of both his product and the superb support they provide.
Highly recommended and a beacon in terms of quality of product and service which other Joomla developers should aspire to attain.