What is the best external flash to purchase for my Canon 50D?

I purchased my Canon 50D about 3 months ago and have recently decided I want to purchase an external flash. Are there any suggestions on which would be the best to get?? My budget is about 200 - 350 dollars.What is the best external flash to purchase for my Canon 50D?
';The Best'; flash will be the Canon 580 EX II, hands down, no question.





However, you need to evaluate your definition of ';best.'; Do you mean the best, or do you mean the best one under x amount of money?





The 580 EX II was specifically designed with Canon SLRs in mind. It integrates fully and perfectly for your 50D.What is the best external flash to purchase for my Canon 50D?
The 580EX II is a professional flash intended for very heavy use. It has a lot of features, a lot of power and I believe is fully weather sealed. It will fall towards the top of your budget or over it. If you are looking for something cheaper and more for recreational use check out the 430EX II also a great flash, but it will save you some batteries and be easier to use, not to mention smaller and lighter. Also do yourself a favor and by some duracel rechargeable batteries. They work for at least 1000 charges and work very well every time. Multiply the cost of 4 AA batteries times 1000 and figure out what you save for yourself. I drain them all the time even in the cold weather and the still work fine. You will probably loose them before they die. It will save you a ton of money and help the environment.
I recently got this one for my Canon 50D. It is Sigma 179101 Sigma EF530 DG.





It works great. It has Autozoom function that automatically sets the optimum illumination angle. It covers a focal length from 24mm to 105mm. It covers 17 mm angle with a built-in wide panel.





I found it for $149 with free shipping at dealjuggler.com. Here is the link. The sale was through buy.com.





http://www.dealjuggler.com/Sigma-179101-鈥?/a>





Hope the above was helpful,





Enjoy..
I have to agree with the comment about the 430EXII. However...





The forerunner of the 430EXII - the 430EX - is almost as good, or if you don't need manual controls, ask around for a Canon 420EX. I had one of those for years, and if you don't need the manual controls, it's fine.
For your budget the Canon 430EXII is the best choice. It has a tilt and swivel head so you can bounce the flash or add a diffuser.