Latest firmware has Capture Priority Mode feature that processes images when the buffer is full. At max resolution, 3 photos fills up the buffer which kicks in processing that would take about 10~20 seconds. Yeap be patient like slow cooking.

Dynamic range kinda sucks. SOOC JPEG quality sucks. High ISO performance really sucks. Some claim that its native ISO is only 100, and all other ISO settings are artificially simulated from in-camera post-processing. That explains why ISO 100 looks better than ISO 50. Yes there is noise at ISO 200. Haha gotta love this crazy Foveon!!! Of course there is no face detection. CDAF but manually select only one of 9 point focusing points. What a PITA piece of crap. But I've grown to like it. Foveon sensor is known to give very accurate color information, and it's just amazing how well it captures accurate color in shadow, on water reflection, in bright sun, or whatever crazy condition. Yes I use only ISO 100.

LR4 supports RAW, but Sigma's SPP app is much better at processing RAW. SPP can raise the brightness and boost color very well and simulate standard/vivid/scenary/monochrome/original/etc picture mode. But that's where its usefulness ends. Export to Tiff format then let LR4 import it.

SPP 5.5 has a pretty cool feature. Monochrome option from white balance selection strips out color information and uses only luminance values to produce "pure" B&W photo. FYI CMOS sensor has bayer filter on top of it, applies demosaicing algorithms to interpolate a set of complete red, green, and blue values for each point, then B&W photo can be generated from the guesstimated color information. That is a guesstimate from a guesstimate. Since Foveon sensor has three vertically stacked photodiodes for red/blue/green that collect 3 different luma information for each point, this new feature gives excellent B&W by controlling three different luma value separately without getting color noise. Some call it a poorman's Leica M-Monochrom :)

Example http://forums.dpreview.com/forums/post/51037744

But it supports only SD1 and DP1/2/3 Merrill series. I'm keeping my fingers crossed for expanding SPP's Monochrome support for all other DP series.

About video performance, it sucks.