You can open VPX project files in MEP, and vice versa (they both create .MVP files) but I hope it goes without saying that if you are using a feature that is exclusive to VPX it will not function in MEP, and vice versa.
If you have a particular reason for the question, e.g., you want to know whether you can do "XYZ" in both programs, you need to tell us what are the specifics of your situation.
Thank you, you've largely answered my question. I think I can assume that VPX otherwise covers just about anything MEP can do and more - although I know the former doesn't do takes, for instance, but then neither does MEP do them too well in its recent incarnations. I think it's worthwhile going for VPX since, as you say, the MVP files are common to both.
Almost forgot the little issue of hardware acceleration. I see Magix is now claiming hardware acceleration on export in VPX using NVidia GPUs - but can VPX also use UHD 630 for that purpose, as does MEP? If so, any idea which is the more advisable to use, or are both employed where available in a particular system?
My understanding of Hardware Acceleration in either MEP or VPX is that it is the presence of a GPU within an intel CPU that is the deciding factor. IOW, if the user's CPU includes an iGPU that handles HD 520, or possibly 530 as the minimum then HWA is available. The addition of certain Graphics Cards can allow faster export of certain formats, most notably HEVC, I believe. This page lists the minimum hardware requirements for MEP.
Just as an indication, my CPU includes an HD 530 GPU and I see HWA being used for .mp4 exports. My AMD Radeon GPU is "below" what is suggested on that page, but I do see it "being used" during export.
Sorry, Jeff, positively the last question re VPX (for today!):
Apparently VPX has a facility called "Project Temp Folders", which are useful for conveniently holding clips from a given project. In what form are these clips held in a Project Temp Folder? Are they numbered or indexed in some way, and are they real files (like Takes in MEP) or simply internally linked to the MPV file? Are they thumbnailed in the Project Temp Folder?
The PTF is a bin and contains just the link to the file, otherwise VPX would grind to a halt very quickly. VPX uses the PTF instead of takes, available only in MEP. There is no need to uses takes when you have VPX. You simply insert the clip into the PTF main folder or a subfolder.
Look at the PTF full screen in list view to see everything that is there. The first column is the name, but just like in properties, you can change the name of the clip and add a description. This is only in the program and does not affect the actual file itself.
You can export and import PTF folders from one project to another.
You can put effects on a clip and add it to the PTF. Then you can reuse that clip with effects from the PTF.
You can import to the PTF instead of to the timeline, then put objects on the timeline from the PTF.
Yes, you mentioned the PTF in passing when we discussed the problems I was having with Takes in MEP, a while ago. I actually printed out that thread as it was quite pertinent at the time, and still is.
The link you provided above is also very useful. It would seem to me that the PTF provides a much enhanced alternative to MEP's Takes, although virtually all the detailed information for each clip therein is (for my purposes) superfluous. Nevertheless, there's no doubt that the PTF lends itself very well to my way of editing - as apparently it does to yours, too. Strange that others don't seem to find it of much use: I suspect that has something to do with the raw material we're using; viz. lots of 3-minute Super 8 clips, each of which can be pasted into one (but more likely more) finished movies. I surmise that the more common workflow is to start with only one long video and trim it on the timeline in one shot to produce one much shorter movie.
With that said, I just need to find GBP349 (R7000 sounds even worse)...