It is hard to me to believe GDP will sell for $500 after crowdfunding campaign. It is a 5 inch W10 tablet with fixed battery and a no-light keyboard. I think $500 would be a crazy price, for it. Pyra is differente: more special, more custom-made, with more details (although with lower CPU/SOC).
You can buy Windows 10 tablet with 10 inches screens for little more than $200. So using a 5 inches screen and adding a keyboard doesn't make $500 sense for me.
Of course, if you say: "I offer this for $300 today... if you wait, tomorrow it will cost $500" you attract more people.