How do you evaluate a chamois (padding in shorts) before buying? Stores only allow you try out shorts with an additional layer of underwear because of the hygiene issues. While this is great for public health, it seems to make it impossible to evaluate whether a pair of shorts is comfortable before buying. While it may be possible to return merchandise at some retailers, it would be nice to be able to compare different shorts before buying. The only usable advice I've heard is to always avoid gel padding.

What can I do to "kick the tires" on a pair of bike shorts to get a sense of whether or not the chamois will be comfortable? What should I look for either when looking at a chamois in person or when reading the marketing techno-babble on manufacturer websites (e.g., what the heck is a four-dimensional chamois)? Do more expensive shorts always have better padding, or are there certain styles of chamois that work for some people but not others?

Related questions: What should I look for in a good pair of cycling shorts?, Tights, Shorts, and Padding
I have bought my last few shorts by direct experimentation at stores, and had the same doubts as yours.

Mostly, what has worked is: you dress the shorts, and stand right up with feet in the normal position. In this position, the shorts should not produce a "bulk" between the thighs. Shorts that produce the bulk tend to be too uncomfortable either while on the bike or while walking.

Also, raising each foot alternately while flexing the knees should not produce a rubbing sensation against the inner thighs, which would mean skin irritation.

I have noticed that the padding should not be flat, that is, it should have a saddle shape. That means you cannot easily fold the short to put it in a drawer, for example, and when you hold the shorts by the waist, the short keeps like "inflated".

At last, the overall compression of the fabric should feel "fine" and specifically the elastic bands around the waist and the thighs must feel "right": a gentle compression, not a tight one.

I think that's it, hope it helps!