Nobody can confirm that Nummix is really holding 33.9 BTC like it is currently shown on your website, you are avoiding to answer some concerning question LoyceV asked about it and this is potential red flag for me,
especially when I can't find any real feedback with good or bad review about Nummix service anywhere on the internet.
Service conditions:
Service fee for mixing is just 0.5% + 0.0001 BTC for each recipient's address
Your fees before was 0.1% if I remember correctly, that means you increased them five times in several months if I am not mistaken.
I can't see any real advantage here compared to other mixing services and some of them are working without fees based only on donations.