Strong, I have 2 of their boxes and they are at least as good as the Xiaomi Mi Box S they replaced.
I will edit this later with the models I have.
I have the LEAP S3 and the LEAP S3 Pro, the main difference between the two is that the S3 Pro has 4GB RAM vs 2GB of the S3.
The advantage over the Xiaomi is that both models have 100Mbit/s Ethernet port.
The only issue I had so far is that I use the S3 Pro for TV streaming with my cable operator app, and if it has a pen drive inserted the app keeps freezing every 10s or so for a couple seconds like it would be buffering. No pen, no issues.
I first saw some networking equipment of theirs in a national retailer here in Portugal (Worten). At first I thought they were just another chinese brand but one their equipments caught my attention, was an affordable (55€) 4G LTE desktop-like router that had 2 SIM support, 4-port Eth and a battery, and I investigated the brand. Then found their set-top boxes and I bought the LEAP S3.
If you open their website, choose About Us, Our Partners, you can choose a country and find the local retailers carrying them.