hi, i’ve literally just made the same switch on my hardtail. I spent a lot lot less than that, but I still wondered about spending the cash for quite a while.
The weight bit wasn’t an issue for me, i’m not fit enough, light enough myself, or able to buy light enough components that the weight loss would be a big benefit to me!
However, I switched based on recommendations, and so far i’ve been really pleased with the results. I’ve found that the two chainrings are far more useable for my ‘normal’ riding.
In 3×9 i found i’d be changing on the front a lot, and occasionally i’d get caught out in the wrong chainring. With 2×10 you can use more of the rear gears without changing, so i seem to have a bit more flexibility when i need it. As a practical example, there’s a climb we do locally where i’d have to drop to granny for a couple of sections, but i’d want middle gear for several other sections of it. With 2×10 i can just rack through the gears at the rear for the different sections.
Same with some descents, i can switch up then double change down a couple of times for a steep climb halfway down.
Basically, i really like the change, but it only cost me £200 or so!