As others have said, you really don’t need the adze, esp if you are only making a few chairs. The inshave or even a large gouge can do the job. The adze is like a very rough scrub plane and the inshave more like a traditional fore plane. You’ll be surprised how quickly the inshave will work and you’re really not going all that deep with the saddling anyway. If we were closer, you’d be welcome to try my Tim M or Kestrel. They are both great, I prefer the former and have been close to selling the Kestrel as it isn’t used.
Please take some pics (I know you will!) when you get going.