The outnet is hit and miss. For sure some of it hangs around for a while, but for a specific item at a reasonable price point with reliable delivery and easy returns it can be great. That second dress (the Vince one) - I have a shirt from the same collection, same fabric, new (not from the outnet) probably about 3 years ago, and it's actually really lovely. Very well made and finished and hangs with a lovely drape. It doesn't look or feel cheap at all. But I haven't seen the dress irl.
OP, city law firms, in London at least, aren't particularly staid these days.