Recommended alternatives to run IP 10+ and macOS 27+??

According to https://support.apple.com/en-us/102527, Rosetta2 can still be used with macOS 27, so you're fine for the next year or so at least.

"Note that WaveMetrics does not explicitly support running Igor Pro 10 under ARM emulation, but we may do so in the future." What does this mean vis-a-vis my two choices?

It is possible that there is a bug that happens only when Igor 10 is run under Windows 11 ARM64, and if presented with such a bug we might not attempt to fix it. So far I don't think we've been made aware of any ARM64 specific bugs other than an early bug in the installer, which we quickly fixed.

- For the remote login case, accepting that an Intel or AMD chipset is demanded for IP 10+, what combination of Windows machine + remote login software on the Windows and macOS machines is best recommended to provide the most seamless .... (rest of story above).

Remote login sometimes does strange things with graphics card support. In the past we've had users complain that Gizmo didn't work properly when they were using Igor through remote desktop. I don't recall many recent complaints of this nature, so it's possible the situation has improved. I suspect you would be happier using a Windows ARM64 virtual machine rather than a separate PC with remote desktop, but I don't have any specific recommendations.

Thank you Adam! I was seriously confused about loosing Rosetta on macOS. I can appreciate having another year or so to consider letting go of IP 9 fully. And the interim year ahead should give me adequate time to test all the caveats in transitioning to IP 10 via a Windows emulation.

With my new M5Max MBP I am running IP10 in two ways

Inside real Windows VM. Works great on both Parallels and Fusion. Fusion is free (except Windows license) but less convenient (no Coherence mode when Windows app run without Windows desktop). Annoying part: 30-50GB VM drive on SSD. Booting to Windows takes more time and never ending flood of Windows updates. But I can run other Windows software in it. 

I switched to faster CrossOver and that works mostly well enough. Graphics is bit worse for some reason and even on this, way overpowered, machine graphics seems tiny bit slow. Everything seems to work. Did not check Gizmo yet. Lot smaller memory/SSD footprint, quicker starts and no Windows license to deal with. But, yearly license for Crossover. Did not try the free Wine Crossover is built on, do not want yet another development project. 

Either way, there are ways to run IP10 on Windows just fine. My prior short tests shown that Gizmo was very, very slow, may be due to arm64? No idea...  Have not needed that for some time now. 

Requirement to use workaround adds enough friction that most of my Mac users do not want to deal with it. In some cases they even cannot deal with it - for unknown reason our IT recently banned Parallels (but Fusion is fine...) from our Macs. I know some other National labs users have the same issue - virtualization is generally banned.    

One of my users told me that he was happy to realize, that he will retire before his Mac will stop running Igor 9 ;-)

I use Igor 10 exclusively via CrossOver, too. Unfortunately, a lot of performance is lost, and Gizmo in particular is slow. It works, but rotations and movements are (big) problems. I think translating OpenGL graphics to ARM is the reason. I tested Igor + Crossover on Ubuntu (x86) for a while, and Gizmo ran smoothly there.

However, I recommend changing the Crossover settings so that CMD is recognized as Ctrl and vice versa.

I’m currently testing the preview version of CrossOver, which runs without Rosetta. Gizmo isn’t working at all right now on the preview build (arm64-20260821). I reported the issue to Codeweavers and even received follow-up questions. So I hope this issue can be resolved. Igor's other areas, however, seem to be working well without Rosetta. (Not to mention that the preview version of Crossover 27 is still relatively buggy overall.)
Regarding CrossOver licenses: With the subscription model, you’re essentially purchasing the versions / updates that are released during that time period. If Igor 10 runs stably with version 27, there may be no reason to purchase updates for more than one year.

Alternatively, for a significantly higher price, you can purchase all future updates for life.

Codeweavers now has a relatively large amount of funding thanks to contracts from Valve (Proton and FEX) and Apple (Game Porting Kit). I get the feeling that developments have accelerated significantly. But maybe it's just that the foundation of the translation has become more sophisticated.

I've tried Parallels in the past. But in this case, I find it unacceptable that the standard version has a limit on shared resources (CPU and RAM). Of course, a Windows 11 for ARM license also needs to run on top of that. At the same time, Windows continuously uses system resources in the background, or Igor takes significantly longer to launch. Parallels, in turn, uses Prism. I don't know how well this system works, especially for Gizmo.

For the same reasons as ilavsky, I did not consider using Wine directly.

I just re-read Adam's response and it made me wonder. Considering number of arm64 Windows boxes is growing fast and advertised even by Microsoft... How is Igor doing on native Windows arm64 box? 

If I recall correctly, Qualcomm just put out new chips and number of notebooks with arm64 chip must be growing. What is performance of Igor on such box? Will that force Igor to eventually come with two versions? 

I have a midrange Surface 7 that I got almost a year ago with an ARM64 processor. If I run Igor's benchmark experiment, it is slower for most parts than with my 2020 Intel i7 laptop (which when purchased was a little more expensive than my Surface 7 so it's not a super fair comparison). Slower, but plenty usable. I have not tried to do anything complicated though.

I do not get the sense that the ARM64 Windows laptops are very popular. They are fairly battery efficient but for the most part do not seem like premium devices.

I had a chat with Claude about what kind of performance improvements we might expect if we ported Igor to ARM and I think it said something like 30% improvement in general but the improvement could be higher in certain cases. IMO that's not a lot, and since all XOPs would need to be rebuilt (and possibly heavily modified) it doesn't seem to me like it will be a priority any time soon. We would still need to solve most of the same problems we'd need to solve to have a native version for macOS (maybe not rewriting Gizmo at least).