If it's in a taxable account you'll probably get a K-1, which just adds a little bit of extra fun to your taxes. Not hard or anything, but annoying to wait an extra month or so for the damn thing to arrive, and more data entry to do.
It might beat the market in a bull market, but it'll be less than 3x. And in a bear market it'll be down more than 3x. It won't be symmetrical.
I do own SVXY in my Roth IRA. In normal times, VIX futures are in backwardation, meaning the ETF naturally makes some profit as it rolls contracts forward. It's not all that different than writing calls and puts for the income stream. So long as there isn't a market crash, SVXY will naturally tend to rise. In a crash it will lose significant value quickly. I wouldn't put a huge amount of my net worth into this.