That is quite odd as I have an old FireWire interface which reports better latency but does not feel as immediate. I think if it feels ok then why look for problems. Unless you are having problems with high latency?
By the way I didn’t buy mine to work with Cubase. I bought it for recording to SD card live performances. When I tried it in my studio I found the latency was as good as my old Yamaha n12 so I started to use it. The monitor outs are also great for different headphone mixes.
I use SD3 drums and play them from my td30 kit without noticing latency at 64. I also have no problem playing keyboards in either. It’s not what I would have chosen for my home studio if I didn’t need it for live recordings but it works well for me.