DOMs, where are you primarily looking to wear this watch, and with what sort of clothes? Also, what is your price range?
Main things to take into consideration:
1. If the watch is going to be worn with long sleeve button up shirts or jackets/suits, get a slim watch. You will look like a tool if your clothes bunch up around your watch.
2. Purchase in the correct price range. If you are just looking to have a decent watch for day to day living, there really is no reason to go over $200. If you are looking for a nice general all round watch, the $500 range will suit your needs, and for a nice business class watch, you can keep it around $1000 without being overtly pretentious.
You can get a decent timepiece in the sub $150 with a Fossil. I wouldn't purchase one to wear with a suit however. They have enough makes and models that you could easily find something nice.
Diesel is a good company, but they have shifted their business focus so many times, that I would hesitate to spend any substanital amount.
For a good entry level watch that you can wear anywhere, you absolutely cannot go wrong with a Seiko or a Citizen or Bulova. They are nice, relatively inexpensive and you can get them serviced easily.
In the 1k range you can't beat Movado. Period. Very classy look that will ALWAYS be in style, they hold their value, and go with any decent outfit. Yes I am a little biased, but Movado has always been my favorite brand, and I saved for years to get my first one.
One more tip DOMs. When you are shopping look for previous years models. They wont have them in the showcase often, but you can shave a LOT of money off a watch if you buy the previous years.