I say this with mixed feelings but honestly I just hope they discontinue the battery pack and replace it back with a battery case just like they had before.
I've used both products extensively with my iPhone 7 and iPhone 12, so I know them fairly well. The MagSafe Battery Pack is the one and only Apple device I've bought that I am not 100% happy with.
For starters, it wasn't clear to me how to correctly use the battery pack from the get go (you have better results if you just start the day with it attached and remove it once it's depleted) and it's almost impossible to use it on hot summer days. It just throttles immediately. It's also difficult to do heavy usage with it, with things that warm up the phone a lot, such as when using Maps, as it'll throttle briefly at some point. You will also see this on mildly hot days just by having the phone in your pocket... I've ran into situations where I had it on all day and ended up with 100% battery on the case and my phone dead, because the thing didn't charge due to heat...
With that being said the MagSafe battery is insanely practical and can cover some, or most day to day situations, and I understand that I may be a rather demanding user. But the case did cover for ALL use cases I've thrown it into, so...