The team at thinkworkobserve are very professional designers who take great pride their designs & create beautiful pieces for us to use across our websites/campaigns - always giving fantastic advice too! Nothing really as such but I would say that they can sometimes be slow (in terms or responding) which could possibly lead them not meeting deadlines? Great people though so don't worry about it :) we have used many different agencies over time when creating campaigns etc., this has been one if my favourite ones by far because i feel like all staff members know exactly what you want from your campaign / website development project before hand meaning everything goes much smoother once agreed upon!