I own half a dozen Samsung Galaxy tags, and have a Samsung phone.
I find it works really well. Flying as SLF, it tells me where my luggage is reliably (including whether it's actually been loaded into the right aeroplane!), I recently mislaid my wallet, pulled out my phone, searched for it - and it correctly told me the exact address of the shop I'd left it in. If I've mislaid my keys around the house, I can use the phone to activate the alarm on the tag and track them down without the duty searching.
The system has limitations - it isn't a lot of use in rural areas where there may not be somebody nearby with a Samsung phone it'll talk to, it doesn't always tell you automatically the battery's flat so yu want to check it periodically to make sure, and it takes around a quarter of an hour to update sometimes so wouldn't be brilliant for tracking something moving. But as cheap peace of mind, I'd say worth every penny - I have them on my keys, aircraft keys, headset bag, wallet... You get the idea. It's a cheap insurance policy that I think is really worth every penny.
I think that both the strengths and weaknesses apply similarly to the Apple alternative - so that choice is down to which model phone you've got. There's an independent company called Tile who look good on paper, but seem to be reliant upon there being enough phones around running the app, which I think is likely very variable. Google are supposed to be bringing their own product out this year that'll work with any Android phone - on paper that might be the best solution of all, but I don't think it's available yet.
G