equipment recommendation - What will I be missing with Vivitar 285HV vs. LumoPro LP160 or Canon 580EX?

I'm planning to get a hotshoe flash soon (I currently only have the onboard), and I have narrowed my choice down to several options, but I'm having a hard time deciding which way to go.

ETTL

This is probably the simpler option, and I think I would go ahead and buy the Canon Speedlite 580EX.

This would certainly work, but I have a limited budget, so I am considering a cheap (but decent quality) manual instead.

Manual

Mostly based on the lower cost, I am leaning towards these.

My Question

There are two parts to this... First, is there anything important I'm going to miss by going with a manual flash? From what I can tell it simply makes it easier to use it in auto settings.

Second, is there any significant difference between the LumoPro and the Vivitar? Both are inside my budget, but the price difference is significant, so I want to make sure there's not something I'm missing.

Answer

I just picked up a LumoPro LP160 (about a week ago, in fact). I'm pretty happy with it so far. As Matt indicated, this flash will be manual only, but it works fine as an optical slave (triggered by an onboard flash), and it works fine on the hot-shoe with TTL metering or in manual mode. If you end up getting remote flash triggers (ex: Pocket Wizard or Cactus), this should work fine with those, too.

I've seen reviews that show its flash power at maybe one stop lower than the Canon 580, which is pretty good for $160. Some of the reviews talk about its recycle time (it's slower than the 580), but I haven't had a big problem with that - especially if you use less than 100% power, it doesn't take long at all to recycle. All-in-all, I think it's a steal for the price.

Incidentally, you may also want to add the Sigma EF-530 DG Super to your evaluation list. It's a little more expensive than the LumoPro, but it also adds many of the Canon 580's features (E-TTL II, for example). Again, it's not quite the same as the Canon, but it's close, and it's about half the price. I went with the LumoPro figuring I'd get the benefit of the flash in manual mode for now, and if I decide later that I really need a 580, I can still use the LumoPro as a slave.