From my testing so far, the Beta appears to work well with my 4G based Internet connection at home. However, when I managed to give it a quick test run at my workplace, the beta kept delivering speeds under 1Mbps down in Chrome even though they have a 10Mbps DSL connection.
From further testing at home and setting upload / download limits on my MikroTik router, I found that when I set the upload speed to 512Kbps to match the DSL uplink at my workplace, I am able to replicate the issue here and also uncovered a few other small issues.
With my workplace DSL connection the following is the Beta test followed by the linear test in Chrome with the UK server:
Retest with the German server. As I write this post, I see the up/down rows are swapped on the left. 🙃
I did one more test in Edge and although it performed better than Chrome, the upload and download was still around half the linear download test:
Other observations:
The Beta test does not mention it being a multithread test in the test result. For comparison, the non-beta multithread test mentions "Multithread":
Download tests with a block size under 1MB incorrectly show the KB as MB in the test results page. For example, the following test result on the left shows a test block of 205kB, however in the test results page, it shows "205 MB":
If the download or upload test is unable to fetch all the blocks, it gets stuck. This happened a few times, probably due to the small packet loss on my 4G connection, such as the following screenshot where it endlessly waited here for the final 2 kB block.