Expensive things that end up cheaper
I was talking to a friend about money savings and mentioned that I buy large and quite expensive bottles of dermalogica face wash. She was surprised anyone would spend that on a face wash, but as I pointed out the bottle lasts about a year, it is unusually economical in use, and it's the only thing I use because it's very effective too. Anyway, it turned out my final expense was much less per month than what she was spending on several cheaper products, and they weren't even working that well for her anyway.
I've been trying a few more expensive things recently only to discover that they do often last much longer and also work much better. Not just cosmetics or household chemicals, also certain foods and many other items. I've recently found that more expensive coffee is stronger and thus needs a much smaller quantity in the cup, which means the nicer tasting better quality coffee is price comparative to the cheaper brands.
Anyway, what expensive things do you buy that are worth it because they're either far better and/or much cheaper in the long term?