I have both the adapter you have mentioned (and their Genesis version) and also the Mayflash Genesis Adapter.

The Retrolink adapters are good and a smaller form factor than the Mayflash adapter. The Retrolink adapters were released a few years ago, the Mayflash adapter was released earlier in the year.

The Retrolink Atari adapters and Retrolink Genesis adapters work great with Amiga joysticks. The Atari adapter only offers one fire button, the Genesis Adapter allows for more.

The Mayflash Genesis adapter is great with Amiga joysticks as well. It supports a wider range of buttons and is the only adapter I have had that supports Sega Master System controllers as well.

There has not been any noticeable lag with any of the adapters.

You can use the 2.4ghz version of this controller wirelessly with a PC, but you need a genesis controller to PC adapter to use the receiver it comes with - I've used this one with this controller and can confirm it works: https://www.amazon.com/Mayflash-Drive-Genesis-Controller-Adapter/dp/B00QRZ1HVS