Seems like not many people have these, but anyway FYI I've found that by putting the earpieces in the opposite ear as marked allows a good over-the-ear fit since the loop things then face the same direction as intended. I actually get a better seal this way than hanging down in the as-marked ears (which as mentioned leads to microphonic issues).
Also, with the A161s I used the largest tip since you can push them in as far as you want, but with my ears I have a much better fit with the second-largest ("medium") on these. The loop thing sets a limit with how far you can push them in, which actually makes the smaller tip fit perfectly for me. With a good seal there is a nice amount of outside noise blockage.
Good things about these 'phones are the tips fit on nice and tightly, and the jack is also a little oversized so you have to push it in a little harder than usual, so it is hard to pull out accidentally.