Grin have smaller transactions as Bitcoin and Monero. And will scale better then both coins. But Grins anonymity is way worse than of Monero. To me Grin is a crypto currency with scaling capabilities and not a privacy coin as so many like to name it.
That's certainly true, mate. There's a huge difference between Bitcoin and Monero in terms of transaction activity on the network. As far as other privacy coins are concerned, it seems to me that they'll be unable to outperform Monero in the future. They may be faster and cheaper to use than XMR, but their level of privacy/anonymity is not so good. I'm surprised to know that Grin's privacy level is somewhat poor, compared to Monero. Even DASH is not as private as its proponents claim it to be. The only privacy coin that's close to Monero is Bytecoin (BCN). The rest have a long way to go before they become as rock solid as Monero is right now.
It's still the time where security researchers haven't conducted an analysis of Monero's privacy strength compared to other privacy-oriented cryptocurrencies. A throughout research will bring investor's confidence into Monero. At least, XMR is self-adapting as the network experiences an upgrade (hard fork) every 6 months. If this keeps up, Monero could remain ASIC-resistant and privacy-centric forever. Past efforts of cracking down Monero transactions have eventually failed. CipherTrace has admitted it, as well as, other surveillance/analytics companies and mainstream governments. With no privacy coin being close to Monero privacy-wise, it seems to me that it's the most anonymous cryptocurrency in the world. Just my thoughts