It change the handing feeling, a long stem (52mm and more) will bring a stable feeling, and a shorter (like 48mm) will bring a more twitchy feeling.
i had personally test 48 / 50 and 52, I like the 50 and 52 but not the 48 which is too twitchy, and I like a (semi) mellow handling.
I currently ride the 50 mm version and it feels right, a good middle.
When I dropped from 52 to 50, I noticed the handling was a bit twitchier and also my bike was a bit smaller, which is totally logic because if we take some extreme example between a 47 and a 53 there's 0.25" ! Which is enough to considerably change the feel of a frame, and so the handling in this case.
Some nose manualers says it's easier to get into them with a shorter stem, which is logic too.
Hope it helps.