Personally I don't understand buying a quality gun and a cheap sight/scope.
One of the bad things about cheaper red dot sights, the dot is not clean and crisp. It's like a full moon on a foggy evening. Bright center with a fuzzy ring around it. Low battery hours also.
I'd rather spend more, get a MUCH better sight, and a MUCH better guarantee.
Look into the Holosun, Delta Point Pro, Sig Sauer brands. All of these have great warranties, their dots are solid, crisp dots. Plus, like the Holosun brand, most of their sights run on a standard 2032 battery and have roughly a 20,000 to 50,000 (depending on set brightness) hour battery life..! Plus for a little more money, some have a solar cell on them for when the battery runs low on power. You'll be buying lots'a batteries for cheaper sights.
Another thing to think about. If you wear glasses, or have any eye problems at all, you might find that a "green" dot may be easier to see clearly.
Mike