This is all info I've posted before but someone messaged me today asking where I had posted the comments containing this info. Also, a few users have recently reporting network issues when using Automatic (their ISP's) DNS settings. There are two network settings that everyone should change on their console for optimal performance, DNS and MTU size:

1. Press the home button and select System Settings.
2. Scroll down and select Internet > Internet Settings.
3. Select your Internet connection and then select Change Settings.
4. Select DNS Settings > Manual. If you already have this on Manual but have different DNS servers set, make sure that you are using dns.mitm and prodinfo blanking before changing off 90DNS.
5. Set Primary DNS and Secondary DNS to: 1.1.1.1. 1.0.0.1.
6. Select MTU and enter 1500 (or less if your Internet fragments packets that size, do a ping test).
7. Select Save > OK.

You should now have much better network performance. If you are using WiFi, you should also glance down below Internet > Internet Settings and make sure that you are connecting to Frequency Band: 5Ghz and the highest or least crowded. Usually 149-165 are optimal if your country allows using those channels. If you bought a Japanese Switch, you may have to use Tinfoil Incognito to enable those channels. Using WiFi region code R2 and channel 157, I am able to get around 30 MB/s download speed. Using Ethernet is much better, with my speeds off liberashop reaching over 80 MB/s at times (averaging in the 50-60's).

If you are still experiencing slow speeds in Tinfoil, make sure that your microSD card can sustain 100MB/s writes like a Samsung Pro Plus (most shops will host compressed NSZ files so even if you download speed is only 50 MB/s, your SD card will need to write at close to 100 MB/s if the file is compressed 50%). Most 1 TB cards on the market have issues with sustained write speeds, Amazon's is infamous for dropping to 20 MB/s writes after a few GB. To help mitigate this impact, I would recommend using a build of Tinfoil that has a larger network buffer (so you can download at full speed for longer even if the SD card can't keep up). If you are still having slow Tinfoil downloads, make sure that your network location is actually fast (most smaller/paid shops host off a seedbox or single server that will only give you a few MB/s if you aren't in Europe, so trying a free public option might actually give you better performance) and try testing your network speeds using an uncompressed file to reduce the risk of your SD card being the bottleneck. Sparse base games can't be compressed, so trying to download Borderlands 3 base game only would be a good single-threaded test.

Tinfoil also has a setting in the Options tab to enable multiple downloads at once. You can try setting Threads to 2 or 3 and then download multiple files to see if you get a higher total download speed (and significantly reduce the total time for a large queue to complete). Note that increasing the number of threads and using a larger curl buffer will lower the amount of free RAM for Tinfoil to process other things, so it is recommend to only enable one location at a time in file browser if they are redundant (hosting the same content) and don't browse the New Games tab while downloading (to reduce the risk of Tinfoil running low on memory).