CF type 1 cards are permitted to draw up to a max of 0.07A per spec. CF type 2 cards are allowed to draw up to 0.5A and so those should be avoided. I have noticed some SDXC cards can draw as much as 0.6A and so a 64GB SDXC card potentially could draw nearly 10x more current than even a 512GB type 1 CF card! SD cards consume fewer watts than SSDs but because most SD cards are 3.3V devices (as opposed to 5V devices), the more power hungry SD cards (the very fastest ones) actually draw the same amount of current as an SSD. Regardless, I am finding an SDXC card to have none of the HF issues as my SSD but to put this in proper context, when connected via my Pachanko SATA Reference cable and when powered by my LPS-1, SSD still sounds very good and so I will need to weigh the conveniences and much higher capacity of an SSD vs the slightly better SQ of CF and SD cards when used as a music storage drive. As for the OS, I'm fairly certain I will be going with CF SLC.
Yes, I plan to interface my CF cards via SATA using devices like the following. The top device will be used for my OS drive:
https://i.imgur.com/9Lcqg7jl.jpg
https://i.imgur.com/R8tywIKl.jpg
This is the Lexar reader I am using now to do my testing:
https://i.imgur.com/6LeKTNWl.jpg
Mine connects via USB 3.0 and contains both SD and CF readers and so I can do easy A/B comparisons. I am not presently using an audiophile-grade USB 3.0 cable and so I'm sure SQ could improve further. The nice thing about this reader is that you can power it with an LPS-1 at 5V and not surprisingly, it makes a difference vs the stock switching wall wart and also against a bus-powered reader that I have. I will see how it compares against the internal devices I listed above which connects via the lower latency SATA bus compared to USB. The internal device that I plan to use for my OS drive also contains a replaceable clock and I am intrigued to know whether replacing this clock will result in further improvement.