I have a bad back too and had this same discussion a couple of years ago. As coincidence would have it, I settled on the Lyson Langstroth, of which I am running four. I also tried the double decker 8 frame Paynes poly nuc to start, running two.
Firstly on the double nucs. The bees did well in these, but while in theory, the idea looked perfect, I found them difficult to manage, Mainly because they are not quite as will made as the full hives. The frames were a very tight fit and difficult to move, so after wrestling through the top box, pissing off bees and beekeeper, I was often too irritated to bother with the bottom one. The polystyrene itself is also significantly softer than the Lyson and Honeypaw boxes and was getting quite mangled after a year of use. They also dont have a nice range of fitting accesories, Like an eke or full feeder. I wouldnt go back to them as hives, but have happily converted them into swarm traps and temporary split accomodation.
I have really enjoyed the Lyson Langs and dont regret a thing about them. They are 9 frames, so when full will still be 10% lighter than the Honeypaw. They are well made and have been flawless in performance. I dont find the recess a problem, but a do make a point of giving the rim a puff of smoke to clear it before closing. I might crush a single bee per hive? maybe? On the downside, I think they're a little more expensive than the alternatives and some might want that extra frame.
I was also looking at the Honeypaw. And am still considering one for next year, despite liking the Lyson. My reason here is that it comes in a 10 frame standard, which is precisely double the width of the four frame nucs and I quite like the idea of experimenting with running two nuc boxes on top of the brood box as supers or alternatively being a useful way of running a bouble brood to split three ways and so on. The versitility of having the four frame nuc fit onto the main brood box and under the full feeder and roof really appeals to me. Plus it looks like better value than the Lyson. But either way, I would still happily buy more Lysons, regardless of any side flirtations with the Honeypaw.