The offline storage wallet that I've been using is the Ledger Nano S. It works, is legit, and wasn't too expensive.
One problem I had was that it didn't want to synchronize with the Chrome Ledger app. What worked for me was to switch users on my laptop, download the Chrome app on that computer account, and access the wallet there. I'm guessing that a program on my usual computer account was blocking Ledger somehow.
Also, for Ethereum you might have to change the Contract or Browser settings in the Ethereum wallet app. For some reason the default settings were set up so I couldn't use it, and I had to enable something to be able to log into the wallet on the Chrome app. Seems like a strange choice of default settings, unless there is some technical reason I'm not aware of (which is possible).
One thing that made me slightly uncomfortable is the fact that it's an electronic device with a USB cable, and I figure that repeated use would eventually deteriorate certain parts catastrophically. This is a reasonable fact, and in practice shouldn't be such a problem since I won't be using it more than once a month. But that aspect did make me slightly envy paper storage. In reality, the worst case scenario is that every ten years or more, you buy another one. And ten years from now, the crypto market will likely have made things easier and more accessible anyway.
Thus, it has so far been working, and I have significant holdings on there. It generates random recovery words during setup just in case the building burns down, or I forget my pin number, or the wallet gets stolen, or I drop it in a toilet, et cetera. Next I just need a small metal safe to stick it in, and all should be well.