Yeah, actually, I think 50K on it's first day is really good.
In comparison:
French Kiss' If sold 30K on day 1.
No Sleeves' Answer sold 41K on day 1.
WH - Valentine Kiss sold 45K on day 1.
In that sense, 50K for a new unit is amazing.
I think it's mostly due to pre-orders though and I expect a huge drop for the rest of the week.