These days I really don't browse using Jio 4G. It is practically useless. I have queued up http downloads in Internet Download Accelerator and let it rip for 4 GB.
If you go to spedtest.net, it is loading the data from speedtest.net servers. But once you choose Jio Mumbai as your speedtest server, the data is flowing directly from Jio's own server in Navi Mumbai. That has no data capping so you get full possible speed.
Once you start downloading something from cdn, level1, cogent, telia sonera, Amazon cloud servers, then you hit the bandwidth cap and the speeds are laughable.
Today I downloaded Firefox 49.0.1 full exe installer at an excruciating speed of 24 kBps. I remembered those crappy days of Net9Online and dialup.
I am not complaining as I very much filled up my hard drives in April-June period when I was getting stable 60-70 Mbps downlink.
IMO, if you want the true test of internet speed it should be on the "other servers" and not Reliance's Navi Mumbai or Gurgaon servers.
Content on the internet is not hosted on reliance's servers but on servers around the globe, so it is downright misleading and meaningless to check Jio's speeds on Reliance's servers. It is like connecting to another system on LAN via ethernet and boasting about 100mbps connection speed your computer has, while all content is on the internet on the other side of the router.
It is a false and inaccurate representation of speeds.