The shell is pretty nice and tells you which articulation you have selected and highlights the current key-switch in green. There is reasonable consistency, but since I can't physically edit the samples, I have to 'edit' them in Kontakt and try to get the correct volume by adding or subtracting db for each wave. So not nearly as consistent as samples I can normalize and edit.
To create your instrument, first download the Kontakt shells listed below. Then get the samples from the Philharmonia Orchestra, convert them from mp3 to wave and drop the appropriate waves in the samples folder for each instrument. Now you should have a functioning Kontakt instrument.
So why bother? Well a good free Viola is almost impossible to find. This one sounds quite nice with the only negative on it and the Violin being that the samples max out at about a second and a half. Also the Violin has articulations that the ldk1609 doesn't, especially those 1/4 and 1/2 second notes.
The violin has 1000 samples with five to six velocity layers in 1/4 second, 1/2 second, 1 second and 1 1/2 second notes as well as pizzicato. Also glissando, legato, martelle, spiccato, staccato, tremolo, trill, detache, punta, talon, and tenuto phrases.
The viola has 800 samples with five velocity layers in 1/4 second, 1/2 second, 1 second and 1 1/2 second notes as well as pizzicato. Also a few phrases but fewer and more lightly sampled.
The Philharmonia Orchestra have licensed their samples under a Creative Commons Attribution-ShareAlike 3.0 Unported License. You can use these samples for a Commercial Work. Just give attribution to the Philharmonia Orchestra.