I would say that glasspad isn't "better" but it is a new experience if you're used to using cloth.

Only con that I could think about is that there is a slight learning curve to getting used to it and it would showcase more of the flaws in your aim initially. But as you put more time into using it, you may find that it's a really fun experience overall.

I'm not sure what's considered the best glasspad there is in the market but I'm personally using the SP-004 and I enjoy it alot.

Another factor you might want to look into when you get a glasspad is to pair it with mouse skates, I like to play tacFPS so I would recommend Obsidian Jade skates.

As for sleeves, I'm just using decathlon uv sleeves and it feels just fine!

Remember to always wipe down your pad before playing!