There are lots of threads about these. I had a pair of the tens and regret selling em. I thought they were great, especially for the price. Some people feel the opposite but I much preferred them over the bx 4’s.
I had a pair of 8x42’s and wouldn’t hesitate to recommend them. Glass is on par with the bx4’s or vipers, same price range. They’d be great for a back up/truck set. I upgraded to their B series or I’d still be using them
Highly recommend the C series for sub $750-ish price point. They’re a solid optic. I had a pair a few years back and was more than pleased with their performance. They were the first bino I had used at the time that I could truly sit behind all day without issue. Great color fidelity and solid low light performance. Only drawback was the relatively narrow (comparatively) field of view.
In comparison to the BX series, there’s no comparison. Leupold is last place from my experience. Horrible facial ergonomics and a general “gray” color hue in all leupold glass puts them at the bottom of the totem pole for me. I would buy the C series 10,000 times over before I even considered some Leupolds.
I had C1 8x42 for several years before upgrading. They would make a solid backup pair.
I bought my son the BX-2 10x42’s last year and they were much better then what I thought they would be. They might be something to consider depending on where you’re at on budget.