Prusament refills
To anyone thinking of saving a 'few quid' by buying the Prusament refills instead of the conventional reels - think carefully about how you value your own time.
I thought I'd got a bargain when I bought a couple of refills of my 'go to' filament; Prusament Galaxy Black PETG. However after half a dozen failed prints due to tangled filament jamming on the re-fitted spools I had to spend a couple of hours rewinding the filament onto old spools, struggling to get the end of the filament to stick to the centre of the spool to get it started (I ended up jamming the filament through the holes in the side of the spool), carefully guiding the filament by hand to ensure a neat winding and swearing profusely when the filament jammed again multiple times coming off the re-fitted spool.
So, as well as the wasted filament in the failed prints, I wasted 2-3 hours rewinding the 1½ unused reels ... all for a 'saving' of 2x£3. Prusament is marketed at a premium price (+ significant postage if you have no requirement for accessories to bundle it with) and despite Prusa's assurance that:
"Every Prusament Refill we made is up to the high quality standards of our in-house made filaments and is well-secured for transport, so you don't have to worry about tangled spools".
It may well be 'high quality filament' but the winding isn't - I think ordering off Amazon is the way to go if you want to 'save a few quid'