I have now had an adequate amount of time to use the new Harbor Digital Flash Extender and it really works extremely well and is very easy to install. I have the Better Beamer flash Extender and used it quite a lot for adding fill flash but it was not all that easy to install on my 580 Flash unit. The new Harbor design slips on and off and is also easy to aim. I have use it extensively over the last month and it really does work extremely well and adds a nice soft light, not harsh at all. I do plan on testing it at the various zoom angles to see what pattern of light it provides to see what may be more useful depending on how far away the bird is. I have not removed the inner flash lens as other people have done simply because I have not needed to. This may extend the range even more which would be useful to capture flight images as well as larger birds. I use a Canon 500mm IS f4.0 lens with a Canon Mark IV body that covers most of the ranges I usually photograph birds in. All things considered, I find it the Harbor Flash Unit extremely easy to use and the results are really excellant.

Advantages: I belive that the ease of setting it up on the flash unit ahead of time really works in one's favor since getting set-up in a hurry early in the morning before dawn is sometimes a bit hectic. The Unit is lightweight yet stable and the weight is minimal. The results with this unit are really superb and as I mentioned previously, it gives a nice even light with no hot spots. An excellant product for the price range. I do have one comment and that is there was no information about adding the filters to the flash unit. I have used the daylight flash filters, warming filters, at various times and like the warm soft glow they provide, especially at mid-day in bright sun light.

Disadvantages: As mentioned by other reviewers, the Harbor Digital Flash Unit Extender is not collapsible as is the Better Beamer. Yes, it will take up some space and may be a little bulky but the weight is minimal. That is not a really big problem for me right now but it will take up some space in a camera bag. That is the only real draw back but it is far outweighed by the ease of operation and light weight of the unit.

I carry this in my car all the time and use it in place of the Better Beamer

Advantages: It snaps on to my Nikon 900 without any problems

Disadvantages: For travel by plane, it doesn't fold flat, takes up space

This product is superior to other flash extenders currently available. It provides a more uniform coverage of the entire image area without hot spots or streaks like the more popular brand does. It also leaves no doubt on lens alignment or distance from the flash. On hig end Nikon flashes, it snaps into the mounting ears Nikon uses for their own flash accessories. Many pro bird photographers there days have switched to this for the better quality of light. For maximum effectiveness, remove the insert inside the harbord Designs extender

Advantages: Strong and even illumination
Positive alignment

Disadvantages: Portability is not as good since it doesn't fold flat