Given that most of my cameras are old manual exposure flashes built before the era of built-in flashes, I've had a Sunpak Auto 144PC for ages. It takes deer-in-a-headlight indoor portraits quite reliably, but I had problems gaining a proper understanding of it, and the manual didn't really help me understand it. So I've always felt that using it for anything other than deer-in-a-headlight was really a questionable proposition. It finally started to make sense lately, but with that, the limitations also started to become apparent.
There's a really stupid story in this, by the way. I wanted to move the flash off the camera to gain some separation, but the only cable it came with didn't look like a proper PC cable, so I stored it and thought it wasn't the right cable. I didn't realize that until I picked up the Sunpak Digital Flash and sorted through my cables.
The problem is, the 144PC isn't good for off-camera usage anyway. It only has an automatic mode that puts out the proper amount of light based on being atop the camera, which really doesn't help me most of the time.
So I got the Digital Flash because I figured that the sunpack-cable-to-pc-cable would be the same. Which it isn't, by the way.
Also, the Digital Flash isn't reliable. I took some photos of one of my friends with it and it caused sufficient trouble that I felt that having anybody other than a friend posing with it would be a bad idea. It was just too fiddly.
Which brings us to my next incremental purchase. After reading Strobist, I almost purchased the recommended cheap old Nikon flash. However, I also wanted a flash to be carried around for impromptu situations that I could have better control over, I felt that the Nikon would be too specific to the Nikon cameras.
I compared the Sunpak 144PC, which has been quite reliable, and the Sunpak Digital Flash and figured that I'd give Sunpak a second try, so I got the Auto 383 Super.
The 383 super feels like the 144PC's big brother, except that it makes sense. There's the thyristor settings, where you set the aperture and the flash figures out the lighting for you, and there's the manual setting, where you can incrementally control the power level. It doesn't have the cheap-and-crummy feel that the Digital Flash does. I suspect that the 144PC and the 383 Super were both designed a long time ago and nobody's bothered to update the designs since, which is fine with me.
I also got a Wein Pocket Peanut, which is a neat little piece of hardware. It's a few bits of electronics in a tiny resin package, with a PC plug on the end. For doing wireless flash on the cheap, it's a good alternative to the ebay radio strobes.
Update:Don't buy Wein!
I also opted to get a real stand for at least one of my flashes, so I got a cheap Impact one from B&H and a matching multipurpose umbrella bracket.
With the Digital Flash, if I had a flash on full power, either my Canon A95's built-in or the 144PC, it would trigger sometimes. With an IR filter over the flash, less so. With the Pocket Peanut, at a significant distance, I could still trigger the strobe with the A95's lowest flash setting and an IR filter over it.
I would like to note that leaf shuttered cameras are wonderful things. I was playing with self portraits and wanted to exclude all of the room light, so I just dialed up the shutter on my A95 to 1/500. My main camera, the RB67, has a maximum synch speed (and shutter speed, for that matter) of 1/400.
I found that this setup was actually reliable enough to shoot with people. I use gaffer's tape to attach a piece of white paper to the flash to diffuse the light some, and I use a piece of foam core as a reflector. This gives you the simplest possible lighting setup... one main light and a reflector for fill. It works quite well for a lot of situations, especially taking pictures of people in their personal space.
There's a standard bit of advice that says that you don't need four lights to do flash photography, you really need one light and a good set of modifiers (which they always remind you that you will need anyway. I wouldn't necessarily believe that you can slavishly follow this advice.... but it does not make sense for you to buy four crummy lights just so that you'll have a proper set.
I also found that the 383 Super is really handy on it's own merits. I find that when I take casual pictures indoors, I can usually get a great bounce-flash effect out of it. The swivel head means two very handy things. First, I can bounce flash in portrait orientation... and second, I can bounce it creatively to influence the light in one direction or the other.
My biggest disappointment is PC cords. I probably should have gotten a slave that attaches to the flash hotshoe instead. The cords that Sunpak provides with their flashes are pretty cruddy; the center pin is too thin, so it doesn't reliably attatch to my Pocket Peanut and the RB67's lens, so I end up using the Sunpak Digital Flash to trigger things because the PC cord it came with is a little better built.
Update: The PC cord situation is actually pretty awful. Just assume that you'll be attatching to the hotshoe and you'll stress out less.
I strongly recomend you check out Strobist, as it's kind of the spiritual center of the low-budget off-camera-flash movement.
This series is a time-lagged chronological journey through my off-camera lighting. I write about stuff that happens months after it really happens so I can get it organized, to make sure that I don't writing a glowing review of something that turns out to be a piece of crap later on, and also so that I have time to digest what I just learned.
My goal with my off-camera setup is to be inexpensive (but not cheap) and portable and easy to deal with. It also has to work with my largely film-centric lifestyle.