Yes, if performance + battery is all that he cares. S845 is the best chip for that price & the next cheapest S845 phone is Asus 5Z which costs 22k or so even on sale (but that has a smaller battery). If your friend isn't much concerned by the looks of Poco F1 & its not so premium build (A50 is made of plastic as well but feels more premium), go for it.
Yes.
Most likely Q will be its last major update with MIUI updates for another year or two.
Not much idea about how they are handling the sales but I expect 20-24k for K20 & 26-30k for K20 Pro. K20 has an inferior SoC to Poco, but overall its a better phone due to AMOLED display, better build (even though it has glass back) & more versatile cameras. K20 base variant will likely have 64GB storage, so expect a higher price for 128GB variant. K20 lacks SD card support, so no hope for storage expansion.
Thanks for such an elaborate reply.. I'm thinking maybe POCO is the better option (for me) because of the SoC & POCO 128GB is for Rs 21K & K20 128GB is for 24K
K20 is indeed not that much better than Poco but do take a look at youtube reviews for its design as many don't like its design much.If you can wait till Oct then may be you will get poco 128gb under 19k with discount offers in fk big billion sale. K20 Pro is supposedly much better with even no ads in MIUI just like poco but then its 6gb/128gb version costs ~28k.
I would any day prefer AMOLED & build over a bit better SoC. My primary usage isn't gaming, so S730 is plenty powerful. For media consumption, AMOLED screens are just on a different level compared to IPS ones. Not to forget the big notch of Poco & superior cameras of K20. For a gamer, S845 might satisfy them more though as the difference in GPU performance is a lot (S845 has 2x more powerful GPU).
You certainly won't be doing that on any mobile(I mean 100+ chrome/browser tabs). You will need ram much more than SoC though for heavy browsing so 4gb is bare minimum & even with 6gb ram poco,I think the best you can do is maybe ~30-40 chrome tabs(with heavy content like videos,javascript,animations etc).
The S845 is like 20-25% better in terms of CPU compared to S730 of K20. So that's not a very big difference like GPU. I don't think any phone or laptop can handle 100 tabs without clever RAM management & stuff. So K20 won't cause any issues. Get higher RAM if you really have such habits (maybe start using bookmark functionality, 100 tabs is impractical).