P.S. how do I get my account qualified to comment on classifieds listings.
Done! It would have happened automatically upon submitting your next post, bringing your post count to 20. But we often manually 'bump' people to the same account status.
I have no experience with the Wallner 500 series system. I used to have a couple of Lici ColorStar analyzers, which are considered excellent by anyone who has used them (many call them 'the best', but I think personal preference comes into play at some point, too). They were a European product (made in The Netherlands), so I think they were never quite as popular in the US as they were here in EU. All I can say is that they did work formidably well - within the inherent limitation of any color analyzer. This means that in the end, at some point, it still comes down to two factors: (1) judging color samples by eye, and (2) decent process control.
You might think that in terms of subjective color assessment, a color analyzer somehow takes this out of the equation. Not so. Firstly, you will still have to calibrate the analyzer to a given paper, and this calibration process still involves visually judging a printed sample and comparing it against some standard (e.g. neutral grey). Secondly, what a color analyzer is really good at, is showing you how far a given sample (measurement taken from the projected negative image) deviates from the calibration preset. In practice, this often means that the color analyzer will tell you how far off its sample is from middle grey. This puts you in a similar position as with a light meter in a camera: it'll tell you very accurately what the correct exposure is for an 18% (15% etc.) grey subject. Which is really great, provided that all of the universe you're trying to photograph is this same tone of 18% grey. With a color analyzer, the issue is a little more pronounced, because there's not just variation on the density/lightness axis, but also on each of the three color axes.
After using a color analyzer for a while, you'll come to realize how little of the world you see is a perfectly average 18% grey. Which in itself is perhaps a quite interesting lesson, if you think about it.
As to factor #2, process control: keep in mind that if there's drift in your process parameters, there will be drift in your results. No amount of magic involving a color analyzer will protect you from this. Instead, it'll throw you for a loop and give you plenty of head-scratchers.
Does this make a color analyzer useless? Not per se, but it makes the preference for (or against) using one kind of personal. Yes, a color analyzer can get you in the ballpark pretty quickly, after which you only have to fine-tune the exposure and filtration to get the desired result. Critics (which, I admit, includes myself) will argue that one or two test strips alone get you there just as well. The other area where they can come in pretty handy is variable contrast B&W printing. Since your color analyzer is essentially a color-aware baseboard light intensity meter, you can measure the contrast range of a projected negative and work out the 'correct' paper grade to use. Back when I still had my color analyzers, this was virtually all I used them for. But also in this application, I found that one or two test strips pretty much got me there just the same. So ultimately I ended up preferring to have some more desk space than a couple color analyzers, which were technically excellent machines, but lacked practical value for me.
One caveat in your particular case is that the Philips enlarger is an RGB additive device. IDK how the color analyzer meshes with that. In principle, it shouldn't be an issue; you can just re-interpret the CMY readings into RGB settings. I suspect this will be perfectly good enough. Philips did make a color analyzer specifically for the PCS enlargers. Here in Europe, they pop up fairly regularly on the second hand market. Like most of what Philips made, I bet it was technically excellent, although somewhat eccentric compared to the rest of the world, and made by engineers with no real concept or awareness of the commercial aspects of the market they tried to serve. But that's another story.
One more thing that comes to mind, although less relevant, is that a color analyzer is of very little (actually, no) use if you're going to do much in terms of pre-flashing etc. But since 98% of the people who print color, mostly do only straight prints, this is probably not much of a concern.
I wish I could share some thoughts about the Wallner system specifically, but alas, my knowledge ends with my awareness that it exists.