Happy New Year!
The Terminator I used before was the first generation. I also bought Aune S5 to try I2S into Terminator, but it never worked that well and the issues were not resolve. Long story short, both USB and I2S inputs of the Terminator were not really stable, even with the upgraded DSP board and firmware changes.
Terminator sounds thicker with PCM compared to SA-10, with SA-10 being more resolving. DSD really no comparison - the SA-10 is just too good with DSD. I believe different brands of R2R DACs may sound different with SA-10 when handling PCM.
Other than SQ, what I like most about SA-10 is its USB interface stability and quality - it has galvanic isolation. The past few months I developed my own music server with LPSU, playing music from internal SATA SSD using Win10 IoT Ent LTSC and JPLAY FEMTO. It sounds better compared to SA-10 playing CD and SACD (which is already good), and a lot better than any Linux-based free and paid software.
My suggestion if you want to try other DACs is to consider those with XMOS USB receiver. They are really great.