Horror stories abound on updating the bios.
But if done properly adhering to the instructions of the motherboard manufacturer, there is nothing to be afraid of.
Go through the motherboard manual and read the instructions carefully.
Visit the manufacturer's website and update yourself on any fresh instructions.
Take a print out of the step by step procedure, understand and execute it meticulously.
To guard against any interruptions of power during flashing, make sure that your UPS is in a fully charged condition, cut off the mains power and carry out the flashing under UPS power.
If you have everything ready to go , the whole process should not take more than five minutes (it is usually much less) and make sure that your UPS can run your computer for atleast ten minutes.
Once you successfully flash your bios, your confidence level will certainly go up.The first time I flashed the bios a decade ago, I was really jittery but once it went through without any problems there was no looking back
I regularly flash update my bios and have not encountered any problems so far.
I have to add that I have done the flashing without getting into the OS and I will certainly agree that it increases the risk further.