As of now, Bitrefil seems the most sane ways to make use of our cryptos. I have completely stopped converting my cryptos to cash since that 30% tax was imposed. So as of now, I can't think of any negative point for Bitrefil. It's saving us from huge burdens.
The commission is quite less and the price is quite ok. Especially when considering the taxes, I don't mind paying that extra amount because it's te most economical way of spending your cryptos right now in India.
I don't think it's profitable any more. Especially if you consider the BTC-INR cross rate of India right now. For example, I just saw a 10000₹ gift card on the website is around 0.00531671. If I translate this amount of BTC to INR using WazirX it translates to around 12500₹, the tax saving is 30% but it's on the net gain only which will mean the net amount post tax will be higher than what I am getting on this website.