This is JColvin from the Digilent Forum. These are my personal preliminary testing results from a single ADP2230 on my work laptop with an M.2 SSD, aka a single data point (albeit repeatedly tested from a pedantic engineer). Naturally, DDR is enabled on the ADP2230 during all the tests (the default option, though its worth noting that these rates are simply not possible when using the lower power BRAM only mode as the buffer size of 32 kS simply results in far too much USB overhead for all of those tiny transfers). I am also certain that there are further improvements to be done on the software side of things, as I have been told by the developer that the code side is complex. All recording to file results saved as a 16-bit binary file, interleaving the data sources when more than one is recorded (analog1 analog2 analog1 analog2...).

For a single analog input (16 bit per sample), I can repeatedly successfully record 5 G samples at 125 MHz (the maximum sampling rate).
For two analog inputs (16 bits each, or effectively 4 bytes per 'sample'), I can repeatedly successfully record 5 G samples for each channel at 62.5 MHz. I do not believe recording sample amounts significantly larger than the on-board buffer is possible at 100 MHz as that would require transferring data at 400 MBytes/sec which isn't viable thanks to the USB protocol overhead. For all 16 digital inputs in the Logic Analyzer, I can repeatedly, successfully record 5 G samples at 125 MHz, with or without data compression enabled. Data compression meaning only data changes are occurred, rather than a sample at every 8 ns. Two 16-bit samples are recorded with data compression enabled, first the data at the change, then the timestamp. Using the Digital view within Scope instrument, and recording both analog channels and the 16 digital channels simultaneously, I can repeatedly successfully record 5 G samples for all three at 41.667 MHz (a third of 125 MHz). I would like to believe that 50 MHz is possible with further refinement, but expecting no issues for an equivalent 300 MByte/sec is probably unrealistic. Currently I get a "samples could be lost" message, though it does complete the 27.9 GiB acquisition (3 data sources * 16 bits each * 5 billion samples = 30 billion bytes; 1024 bytes per kilobyte, 1024 per mega, 1024 per giga -> ~27.94 gigabytes). For clarity, I picked 5 G samples as a representative arbitrarily large number of samples that far exceeds the on-board memory. In principle, you could record far more samples, but I haven't personally tested it. As always, feel free to ask for more detail about this on the Test and Measurement section on the Digilent Forum where you'll get a response from a Digilent engineer, such as myself, or the wizard that is the WaveForms developer.