Arduino Pro Micro alternatives

[JohanAR]

I was looking to buy some tiny microcontrollers for keyboard building and noticed that the Pro Micro is quite expensive in Sweden. This led me to start looking at Arduino compatible boards with the same MCU and an USB port, however I'm quite uncertain if it's safe to assume they can be used as USB HID devices. Anyone have experience with any of the following devices?

A-star 32U4 Micro. I'm guessing this should word as the docs mention USB HID but it would be nice to know for sure before ordering. I can buy this in Sweden for about hafl the price of a Pro Micro
https://www.pololu.com/product/3101

BS PMicro. Looks like a smaller version of the Pro Micro and I'm thinking that if I'm going to order from abroad I might as well get the smallest one. Fewer digital pins but enough for me. Says "Leonardo compatible" but not much info available.
https://www.banggood.com/ATMega32U4-BS-PMicro-Pro-Micro-Leonardo-Arduino-Compatible-Development-Board-p-1176260.html

[Findecanor]

The original Pro Micro from SparkFun can be pricey when shipping to Sweden is included, but because the design is Open Hardware there are lots of Chinese clones around and those are very cheap.
The first I find on eBay is priced at less than 30 SEK including shipping. The only drawback is that shipping from China often is six weeks or so where as USPS from the USA is one.

[spindle]

As long as the boards have an ATmega32u4 you should be fine running TMK/QMK on them.  The main noticeable difference that you will find with different boards is the bootloader that comes pre-programmed as the bootloader determines how you will upload new code to the controller.

Both the boards you linked would come with same bootloader as the pro micro (Caterina bootloader), so the process to upload code should be essentially the same. Their are lots of guides for how to do that with TMK, so it should be pretty straight forward.

[JohanAR]

Thanks for your replies!