Does anyone use VM for the different OS X versions? If so what app would you recommend and do they work well enough in a VM to represent an actual machine?
I’m thinking of using some VMs instead of a external boot drive and a spare machine, especially as some of the problems we’ve had with OS X Cap don’t show on our testing machines 
can’t you use BOOT CAMP for that?
We use VMware Fusion Pro 8.1 on OS X 10.11.4 and find it very helpful for testing different versions of OS X, including 10.11.4 without any other software installed. We also use it for different versions of Windows and Ubuntu.
Beyond general testing with clean installs of different versions of different operating systems, we have one or more virtual machines built to emulate as best as possible the systems our clients are running. Their servers, workstation images and network configurations are emulated for development and testing prior to submitting apps to be tested on their test networks which eventually make it to their production networks.
Virtualization is a wonderful thing, regardless of your preferred tools. Our preference is the VMware family of virtualization products.
[quote=261517:@Sam Rowlands]Does anyone use VM for the different OS X versions? If so what app would you recommend and do they work well enough in a VM to represent an actual machine?
[/quote]
10.6, 10.7 and 10.8
And yes pretty much
Best thing is you can return them to stock installs really easy
Thats for Windows
But with the right machine you can just reboot
I do a bit of both on my 2012 rMBP
Ummmmm… I thought BOOT CAMP could be used to boot almost any compatible OS, Windows, Linux, and therefore other versions of OSX as well… but then I have been wrong on at least one previous occasion, albeit years ago 
I WAS wrong… you don’t need BOOTCAMP, you don’t need ANY VM… just created as many bootable partitions as you want and install whatever version of OSX on each one as required. Google it, there are dozens of websites that show step by step how to do it…
Thanks for the information, I’ve been doing it this way for years, but what I’d like to not have to reboot.
Out of the fleet of Macs we have in our SOHO, only one exhibits the Core Image show stopper that we encountered last year. It’s my coding machine and I don’t like to meddle with it. But I would like access to various OS X installations whilst still being able to work in a stable and reliable version of the Mac OS. SO my thinking was to set-up some VMs on the machine, that way I can remote debug to a VM of any OS, on the same machine, then I can test macOS 10.12 without worrying about it screwing up my dev machine.
I just wanted to see what others think about this plan and what software people recommend.
Well for Windows, I use BootCamp.
One of my sisters uses VM Fusion
and the other sister uses Parallels
and both of them swear by it and swear AT it …
My biggest issue is that you have to reinstall either VM when you upgrade the host OSX…
and before I went to BC I was using Parallels, but one of their upgrades decided to wipe out my entire Windows VM image, so they never got another penny of my money. For me it is not an issue anymore, as I have an old MacPro to run Windows on, for those rare occasions.
Something to consider… while you do need to reboot to change versions using this method, you are sure that any anomolies you find are purely due to that version of OSX and not something introduced by the underlying VM…
I’ve never encountered this
VMWare is rock solid. With Parallels you have to pay for updates very often. There is a free alternative. But that didn’t work with my Wacom tablett at all so it got deleted very fast.
No. I’m using VM and never needed to do that either.
you need to UPDATE the VM application (parallels or fusion or even virtualbox) each time you make a major upgrade of the operating system, but not reinstall the virtual machine.
VMware Fusion with a load of VMs. Before I start testing, I make a quick copy of the VM and test on that, deleting when I’ve finished. This way I always have a set of clean installs.
It’s never going to be quite as good as testing on an actual machine but it’s far more practical and it’s great for catching edge cases, especially differences between, say, the Mountain Lion era and El Cap.
I regularly use VMWare Fusion to test under previous versions. I never had to reinstall the VMs when upgrading it.
With an SSD, speed is correct. With a regular hard drive, it is not usable IMO. In that case I would recommend multiple boot instead.
Thanks Guys, good to know that other developers are doing this.
One more question; Remote debugging, does it work and how well does it work? Right now I’m remote debugging over Wifi and it’s a little too slow for my liking, would I see much improvement over a VM?
Sorry one last question… WMWare Fusion 8 or 8 Pro? It doesn’t seem like I need the pro features (according to what I understand from their ‘compare’ page), but am I missing something that would really benefit me for working in Xojo?
You will see much improvement on the VM. IMO, it’s the best way to do remote debugging if you can do it.
I just use VMWare Fusion 8. Never needed pro.
In my experience Bob is 100% on target.
I had pro in VMWare 7 and found absolutely no need for the additions.
version 8 standard works flawlessly with a multitude of OS on my lovely 17" MBP.
I have found VMWare to be anonymous in use completely.
A big issue with OS X under VMs: the video drivers aren’t very good, so many OpenGL/OpenCL things (and ultimately a lot of OS X features) don’t work, or are software rendered instead of using hardware.
I don’t know if Core Image would function differently in a VM but it sure might.
A quick way to test this is go to the Screen Savers control panel, and under most OS X VM situations you’ll see many of them don’t work.