Frost free fridge freezers – more problematic than manual defrost?

Hello!
I would appreciate some advice. I bought a mark-down Liebherr 4313 fridge freezer in February from John Lewis ( assured cheaper only because of a few bumps on the door).
4 weeks later the fridge section stopped working but then got back to temperature a day later.

I have arranged for refund and collection this week as I suspect it has an intermittent fault as well as the bumps, but now I don’t know whether I should buy a new Liebherr 4313 (liked the fridge a lot when it was working…).

I’ve done some web reading about frost free technology and it seems that there’s loads of things that can go wrong, plus sometimes having to pull the beast out to get rid of ice buildup at the back?

So, I’m now wondering what to do…
buy another frost free or go back to a manual defrost one which seems to have less to go wrong – I had an old Zanussi for years. Not very efficient but at least it lasted!
Are frost free fridge freezers generally as reliable as manual defrosts?

And does anyone have any advice about this particular Liebherr model – are they problematic in particular?

I’ve just moved house so my budget isn’t big but could go to about £500.

Thanks for any input