The LumoPro LP120 manual flash is interesting for two major reasons.
First, it defies the design logic of the big camera companies. They want to sell snazzy proprietary technologies, like through-the-lens (TTL) metering. This flash generally omits them. The big companies also want to exclude low-cost, useful features from cheap products. That way, they can drive people to buy more expensive ones. For instance, Canon doesn’t include a PC-connection on its US$275 430 EX II flash, but it does on the US$400 580 EX II. The LP120 includes a built-in PC connector, hotshoe connector, 1/8″ jack, and an integrated optical slave. It also has output roughly comparable to the 430 EX II, for US$130.
Second, it seems that the flash was designed primarily to serve a single web-based community: the talented and flash-obsessed photographers at Strobist. That seems like the kind of thing that could produce a very clever trend, where like-minded people assemble with specific needs and niche products are developed to accommodate them effectively.
In any case, I am strongly considering getting an LP120 as a second flash. It would let me do more elaborate things than are possible using just a single flash and an umbrella. I have an upcoming photographic project where better portrait capabilities would be a distinct asset.
[Update: 24 March 2009] I got the LP120 flash today. My first impression is that it feels cheap. The battery compartment is finicky, and flash head doesn’t lock in place, and the flash emits a constant high-pitched whine when on. It certainly shows me part of why people shell out money for flashes like the Canon 430EX II.
We will see whether the photographic performance of the flash is better than the build quality.