@Sanemi It is better to ask people in your locality because your mileage may vary. But if you ask me, in the last ~1.5 years that I have been using BSNL FTTH, the experience was overall above average. In the last 6 months specifically, I have not faced any major downtime, my connection was down for only 5-10 minutes max (around 10-11 times in 6 months), expect for a couple of times when the fiber lines were cut and I was out for 3-4 hours (I know the LCO, he is a cool guy).
As for speeds, I think BSNL has improved a lot this year, previously during the peak hours sites like youtube, facebook, instagram, etc would work fine but everything else would get throttled sometimes. Now, I don't remember seeing it more than a couple of times this year.
Routing is also decent, sub 20ms pings to all major servies during mornings and even during peak times, not exceding more than ~30-35 ms. I seldom play games these days but pings are around 40-45ms to mumbai servers, for delhi i have even seen 14-15ms on mobile games over wifi.