I had a Gold Tone for a while. Concert body --tenor scale neck. At times it sounded ok for the price. At times its sounded dull, almost dead. I sold it.
I have had the chance to handle/hear the Kala, several Nationals, have seen Del Ray in person. Prefer the wood resonators. The metal resonators have the bell tone which is nice.....to a point........I like the wood tone resonators better.
I bought a Pohaku Resonator. It's has a maple body and a bolt on neck. A little on the heavy side compared to other ukes. Some previous issues talked about with high action at 12th fret. I have not done anything about that, might never.
I really like the Pohaku overall, quality build, I like the sound--I can hear and feel it resonate.
I really could not see myself spending the money on the National even though I liked ones I did handle and play.
The Pohaku was a price I found affordable to me.
Baz had several reviews of Resonators,,,,check out Got A Ukulele.