Hi @machinemoney,
It’s all about your expectations in terms of how fast you need to be cutting metals. Shapeokos have been cutting metal since a time when the various upgrades did not exist yet, BUT it also required a lot of caution/care in setting up the job.
Here’s me back in the day hogging aluminium on my SO3:
Admittedly at the time my SO3 was modded with a metal bed, HDZ and spindle. You already have the HDZ which is good, the router vs spindle is manageable if you check the runtout on your router, and the XXL vs std size is also manageable if you make sure you bed is properly supported and does not sag, there are lost of posts about adressing that.
At the end of the day, obviously you are never going to but ripping at aluminium the way the HDM owners now do, but if you are ready to take it easy (on the chipload/depth of cut) and don’t expect crazy tolerances, then small batch production of aluminium parts on a SO3 XXL is definitely possible and lots of possible have done it.
Steel, that is another story. Again, doable but you’ll have to be very conservative. You can find examples of SO3 owners cutting steel, but to be honest they tend to be very knowledgeable about their machine and its capabilities, and know how to avoid the pitfalls of trying to do this on a machine that is certainly not designed to deal with that specific material 