The more backers we get, the easier delivering this hardware will be. I won't try to convince you of anything you can't be convinced of, but I will tell you that if you are interested I would really appreciate your support, and as per the kickstarter terms of service I can at least promise that if what we are delivering does not meet your needs, you can cancel your order and we will refund the full amount.
The EULA does require me to either deliver or refund you, and I absolutely will comply with that.
I'd also suggest waiting to see? You could back us at $25 so you get the updates, and then cancel before it finishes if you would prefer not to spend any money at all.
And yeah, the radio chip is pretty simple. It's basically a cheap general purpose radio. The other proprietary chip is the Atmel ATSHA204, which you don't even need to use, but provides some excellent cryptographic functions.
Either way, I look forward to winning you over at some point, even if that's not till the products ship and the reviews are in! :)
This (Flutter) is using a Cortex-M ARM chip, which is entirely different. These are used in small, embedded devices. Like wireless headphones, or robotics. Cortex-M chips don't have TrustZone.
Also, I don't feel comfortable donating before a finalized hardware design is reached. I feel the potential for bait-and-switch is too high and no words will convince me otherwise due to the nature of crowd-sourcing EULA, sorry.