Customizable Crypto Algorithms in Hardware
Your doubts are absolutely valid. Disguising the algorithm is not a valid argument for security. It also contradicts to Kerckhoffs Law. 


  It (the algorithm) should not require secrecy, and it should not be a problem if it falls into enemy hands;


Designing cryptographic algorithms (ciphers, hashfunctions, ...) is a long and complicated process. In academia such algorithms are proposed and are analyzed afterwards by other researchers for a long time trying to break them. For AES, it took about two years from publishing to standardization.

If you take a look at linear or differential cryptanalysis, you will notice that innocent looking S-boxes for example can be highly biased reducing the cipher's security drastically. Same applies to other parts of the cipher.

This contradicts highly to the promised security. I would not trust these algorithms at all, nor a machine designing them.

For the hardware part. They could use some sort of FPGA-based HW. This would allow the company to implement the different algorithms on the same boards easily. Speed is a valid point. However, I doubt that their generated algorithms are side-channel proof, which means one could get information about the algorithm itself or the payload that gets en-/decrypted by measuring power, timing or EM for example. If so, the point of "unkown algorithm" would be broken.

TL;DR


Hiding the algorithm is not a good idea.
Refrain from inventing your own crypto.
Do not trust companies that break both :P


Hope this helps