You do need to make sure that Paterson reels are ABSOLUTELY dry* before loading, and 120 is always a touch more tricky as it's more floppy, but basically it's not hard.

* If I'm developing a second film with the same reel, I dry the reel with a hairdryer first. it took me a very long time to realise that even slightly damp reels are close to impossible to load, whereas dry ones are simple.