You are correct. Apples to apples comparisons are very difficult to impossible. AND the performance of the hearing aids will be different from individual to individual even if their audiograms are identical. So it is important to make use of the trial periods.

You have done your homework because you already know the features to look for. Happy to see you know about hearing loops. I think the t-coils are important. The BTEs are most commonly prescribed for people with your degree of hearing loss. I have used them for many years. Each time I get a new pair I have great expectations but the performance never seems to live up to the advertisement. They are hearing aids and only capable of doing a limited amount of fixing our hearing.

Most recently I tried the Oticon More and Phonak Paradise in a side-by-side trial for 3 months. I have high frequency sensorineural in the severe to profound range along with tinnitus. The Oticon More worked seamlessly connecting to all the devices and were very intuitive to manage. The Phonak Paradise had more connective features allowing them to connect to multiple devices. The Phonak enabled me to hear very slightly better. The downside of the Phonak was that they randomly dropped connections and changed programs without any input from me. Their phone app was terrible compared to the Oticon. Both hearing aids were the rechargeable but the battery life on the Oticons was about 30% longer than the Phonaks, but other were acceptable.

In the end I chose the Oticon More. The sound was more pleasant and music sounded better. I was told that the Phonaks dropping connections is a result of using Bluetooth LE (low energy). I don't believe they have the technology perfected yet. Maybe they have fixed it and maybe the next generation will be better. The phone app that I use to control the haring aids is much better with the Oticon but I hear Phonak has improved their app since I tried it a few months ago. (it needed a LOT of improvement)

Hope this helps. It is a hard choice. Your audiologist will make a recommendation based on his/her experience but be aware that all people are different and will have different results. Make sure you get a generous trial period.

And lastly since these are yours first hearing aids be prepared for a long acclimation period. Your brain has not heard many sounds for many years and may not recognize what they are when the sound is delivered by the heating aids. It can take somewhere from weeks to months for hat to happen.