Just throwing in my 2 cents, I’ve used the Resound Phone Clip+, the Signia/Rexton Streamline Mic / Smart Mic, and the Phonak Com Pilot 2.
I like a strong, robust connection to multiple devices at one time, so that leaves out the Signia/Rexton device.
Both Resound and the Phonak work well, but the Phonak has more features. It can connect to two phones plus one other Bluetooth device, so you can be connected to two phones and still stream from a third device. Also, the Com Pilot 2 has an audio in port. And, you can connect a lapel Mic to it, and that’s what I do. Since it announces caller ID, and has a lapel Mic in place all day, I keep the Com Pilot2 under my shirt and i never take my phone out of my pocket unless I make a call or play a game. It also has a very long battery life. I think the spec is 20 hours. I have done some heavy streaming and phone use with Webex meetings, and it has never run down.
By the way, Signia and Oticon use the same device. I don’t know which one developed it or maybe they both bought it from another developer. I think the Oticon version has the same limitations and performance as the Signia/Rexton version.