What IBM offers is probably a lot more coherent and takes better advantage of what the POWER architecture has to offer, such as larger quantities of RAM, the per-node interconnect fabric, faster I/O (not just PCIe), etc (admittedly totally naive here). Plus of course there's z/OS, which I know enough about to respect (and want to play with someday :) ).

Talos basically offers only Linux and a mildly DIY standing-up experience (https://tenfourfox.blogspot.com/2018/05/a-semi-review-of-rap...), although this is likely to be reasonably painless for non-desktop configurations (and perhaps volume orders can come preconfigured).

As a bit of a pet idea I kind of want to colocate one of the 2U or 4U systems for generic web serving and similar duties, but I fear that running a blog/discussion system on such a machine may result in a constant effort (on my part) at keeping discussion focused on the "it's a different architecture, what comp-sci interesting things can we do with it" aspect instead of getting distracted by shallow OCD-meta-security bikeshedding.

(It's kind of sad that the collective consensus about new/different architectures has to always be about security nowadays, and not about unbiased exploration, which is what we're best at)