Yes, that's what I do, but several have succumbed to the rash of small business owners closing because of lockdowns/lack of employees, etc. I'm reluctant to use a mail=order supplier for a variety of reasons.
It makes a discernible difference IMO, but either type blade is OK if you replace the blades as needed, which isn't easy to do on bargain-priced grinders. That's why I usually get the roaster to grind small batches for me on demand. Storing larger amounts defeats the purpose of using freshly ground beans.
No doubt. I have dozens of vintage teapots for exactly that reason. The composition, design, and manufacturing have to be consistent, and the news ones just don't measure up.
There's a real decline in quality. The new ones craze, even though I always pre-heat before use, and the spouts are inconsistent, so the new ones tend to leak and dribble.