Consider your lifestyle
I do suggest having different watches for both work and play if your lifestyle merits it or you simply like having variety. However, when buying a dressier watch, you should choose something that is classic or more lasting. Personally, I am not a big fan of sporty/technical watches even if they usually tend to cost less and has a night-vision feature, measures distances, calculates altitude, has a compass.
A Stainless-Steel Bracelet
Stainless steel is more practical than leather and is certainly more durable. It's dressy enough to be worn with a business suit and casual enough for other occasions. So not only is it versatile, but it's also waterproof. You could always go for gold if you wanted to drop some serious cash, but be careful since it might give off an unfavorable impression.
Imagine a watch that not only tells you the time, but also has the role of a real bracelet. This is an excellent idea that makes even more happier a woman.
Another thing that gets me when it comes to watches is the size and colour of the watch face relative to the wrist that's wearing it. Watch makers are continually coming out with watches that have larger than standard faces. In fact, it has become quite a trend. There is a trend to have dials and straps in exciting colors. Save the trendy colors for a second or third watch if you must, as it is more difficult to combine.