Is there a better alternative?

Yes, the RTX 3060 Ti is a better alternative. However, given the prices of graphics cards and the difficulty in finding them, the list price doesn’t mean much. If the RX 6600 XT price ends up between the RTX 3060 and RTX 3060 Ti, it’s a great 1080p card for high refresh rate monitors.

　　The other alternative is the RX 6700 XT, which outclasses even the RTX 3060 Ti, though at a premium.

　　

How long will it last?

The RX 6600 XT should last for the next several years for 1080p gaming. If you want to use features like ray tracing or upgrade to a higher resolution, you will probably feel the weaknesses of the RX 6600 XT within a few years.

　　

Should you buy it?

Yes. The RX 6600 XT is about $30 too expensive, but it’s still much cheaper than any other card you can buy right now. If you miss the launch boom, however, consider upgrading to the RTX 3060 Ti instead if you can find it for a decent price.