The two-bolts-in-back-two-in-base on each side design has seen the most success for me in the long term.

I use a socket and ratchet to tighten up the bolts because it's been my experience that if those fasteners are not as tight as they can be without stripping then the chair will loosen up and fail sooner than it would have if those bolts were good and tight.

Note that when the instructions says "keep the bolts loosely secured" keep them loose since it's for a reason.

Assembly by myself took approximately 20 minutes, following the instructions and leaving the bolts loose until all 8 of them in place made it a breeze.

The lumbar support dial doesn't seem to do anything other than entertain my toddler and the bolts keep falling out of the boltholes for the armrest, as if the holes have been stripped

The bolts are misaligned so the chair wobbles a bit from side to side.

No loose bolts, appears the wood has split.

Everything fits, and when bolted together, it feels solid

A bolt that I don't know where it belong fell out

I was hoping it was loose bolts again

Last thing regarding the bolts - and the holes they thread into - one or the other aren't formed such that the bolts, at least on my chair, go straight into the holes; the heads seem to 'walk around in a circle' a bit as they're being driven in - but that's not to say that anything was cross-threaded.

It means they're aware that loose bolts are a problem.

The bolts are separated into individual bags and this made it easy to identify the correct bolts (again, even my kid could discern between "A" and "B" bags)