Purchasing the Teensy 4.1 is much cheaper then the M8, but it requires some tech skill to install and it’s not portable as the M8, as you’ll need a computer to connect it to to use it with a keyboard and screen. On the other side if you don’t care about full portability, it is very useful to familiarize with the Dirtywave M8 software and decide if it’s for you or not without investing 600€ in the full M8 standalone device. The OS is identical, so if you then want to switch from the Teensy to the M8 hardware you’ll have already learned the basics of navigation and editing. to get yourself a Teensey you can either search on eBay or purchase directly on their official website: https://www.pjrc.com/store/teensy41.html