Yes I would say nextra is the best, good quality high speed service provider in the market right now I am using it in my office . there fiber quality is the best.
service support is also good.
they have custom plans u can adjust your data limits according to your usage .Speed may get slow after your limit to 512kbps plan, yes its very costly but the best .
now they have updated there plans previously they provide 1200rs plan with 25gb only but recently they have changed it to 50gb
I am using 75gb plan right which costs me around rs1600.
If you can pay more and want to get rid of connection problems you can go with this broadband.