Daniel,

The time limits apply regardless of which virtualization software you use. If you delete and reinstall the VMs from scratch, then the time limit starts over. The rearms are meant to give you 90 days usage so you don't have to create a new VM over & over within a short period of time. 

Ultimately, if you want to not have time limits, then you'll need to purchase a fully licensed copy of Windows. We're providing these images as a tool to allow you to test browser versions without having to purchase multiple copies of Windows.