Agree, in fact I wrote MCP79 is SATA2 controller, it's not said that every Sandisk SSD will negotiate 3 Gbps, probably the most recent you buy today could give 1,5 Gbps , while instead older controllers work better with older logic boards.
Theoretically you could buy the same SSD you use on MBP 2010, but that's MCP89 AHCI a new revision, but I said between lines, you can buy even the cheapest SSD for your mini and it will work, but probably at 1.5 Gbps Negotiated speed that is half of its capability and efficiency. Even on amazon products reviews you can find advices for old macs using newer SSDs.
The most important feature to me when installing a SATA SSD into an old mac is Negotiated Link Speed rather than "Link Speed" (that is a fixed value based on the logic board controller).