virtualbox.org

I have several Virtualbox installation, without guest additions because they're not free for commercial use.
I'd like to keep my VMs on a external usb pendrive, because I'd like to use them on different pc when I need to.
If I have the vm files on a usb pendrive, do the guest will be slow because the usb 2.0 and usb 3.0 missing (because the additions missing)?
I'm doing some experiments on an usb file vm: as I try to disable the usb support, for the guest, I get an error and a warning telling me I cannot disable, and the enable check will turn on automaticaly, does this mean I will face a big bottleneck?
Thanks a lot

You are confusing the Guest Additions (driver bundles for supported guest OSs, which have nothing to do with providing USB support), with the Extension Pack - additional DLLs for the VirtualBox host software, which does add USB2/USB3 support and other non-GPL things to VirtualBox. The GAs are GPL.

You can access any host drive using a shared folder (requires GAs) or a network folder.

VirtualBox does not need GUEST USB support in order to run a VM from a host drive, regardless of the technology the host uses to access that drive.

Yes, any VM running from a USB flash drive will be slow, especially if it's only USB2. They may also crash a lot, the flash drives overheat and and occasionally corrupt itself. Flash drives are really only intended to transport data, they are not usually designed for extended use with continuous writes. That's why you also have to be careful about using them for time shifting in a smart TV.

Thanks for the clarification, it's true, now I get the difference between "guest additions" and "extension pack".
Nice to know usb support is not facing the wm files location, even if it's an usb itself.