I have both and they are great in different ways - personally I prefer the OP-1 though I was super stoked with the OP-Z for the first 6 months… it just seemed out of this world and refreshing not to have a screen so I need to get back to it and spend time with the new updates and sample more because this makes a considerable difference.
They work very well together. In some ways the sound overlapped quite a lot until the latest update on the OP-Z which has a much nicer reverb and chorus FX. The sequencer on the OP-Z is truly innovative and the possibilities are so vast your head will explode. Atleast mine did.
I barely use the ‘media’ side of the OP-Z but it can also be a lot of fun - sequencing photos of my cat doing crazy shit around the house for example.
So far so good in terms of build quality too. Having read quite a lot of bad things I do worry about it lasting but it feels quite solid to me.
The OP-1 IS rock solid after 6 years of regular use and the battery life is still very good.
I take them both pretty much everywhere I travel and there’s always a point when I start laughing while using them… they’re so quirky it’s hard not to be amused one way or another.
I don’t think it matters which you get - there’s a lot to enjoy. If you’re lucky enough to get both then you’re in for a ride.