There's a LOT of varying opinion on radar reflectors. I'd do a good bit of reading before purchasing one. Much of what I've read seems to indicate that if the reflector isn't active its of minimal real-world use. It might be better than nothing, but not by much - and highly dependent on circumstances (e.g. heel of boat, how the reflector is hung, angle at which the pinging radar comes at the reflector, weather, etc.)
Here's a recent thread that includes a posting by me with a screenshot of what a Davis reflector looks like on radar on a clear day. Essentially, in that one instance (so its a data point/anecdote, not a study) the boat didn't paint any differently than any other sailboats around, and was significantly smaller on radar than a buoy. The radar was zoomed in so you won't see the other boats, but they all painted about the same.
https://forums.sailboatowners.com/index.php?threads/attaching-radar-reflector.197483/#post-1546349
YMMV, and I own a reflector myself which I would hoist in times of limited visibility, but I would temper your expectations as to the REAL value of it, and if at all possible, get a friend to turn on their radar and screenshot you at varying ranges and angles to see what you REALLY look like, not what a manufacturer puts in their ads.