Although it is a little dated, this video from Zack Freedman on Youtube explains the benefits of the Teensy microcontrollers, why the Teensys outperform the Arduino Uno, Mega, and even the Portenta in memory, size, and sheer power, and how the Teensy can be programmed using the Arduino IDE using the Teensyduino Board Manager.
The PJRC Teensy 4.1 (and a couple of other microcontrollers we carry) is featured in EE Times' article on the 10 best microcontrollers on the market. https://www.eetimes.com/10-best-microcontrollers-on-the-market/
The Teensy 4.1 from PJRC is now in stock and ready to ship from Envistia Mall. Teensy 4.1 features an ARM Cortex-M7 processor at 600 MHz. Actual size is 2.4 by 0.7 inch, same form-factor as Teensy 3.6. It uses the same processor as Teensy 4.0, but provides greater I/O capability, including an ethernet PHY, SD card socket, and USB host port. Teensy 4.1 also comes with 4X larger flash memory, and has 2 locations to optionally add more memory. Not every project requires so much I/O or extra memory. Teensy 4.0 fills those needs. But when you do need more I/O,...