I'll bite .... We don't have a C1100 but we do have a C1085 which is the same family from KM, same build but with lower print speed of 85 copies a minute instead of 100 copies a minute.
Textured card I have used is a Conqueror Brilliant White Laid stock I have no problems with. We trialled a pvc electrostatic stock and print quality and gloss were absolutely brilliant.
The only downside I have we use a 300gsm matt stock and the solid ink sections are not good, but having said that using the same stock range in less gsm weights the print results are perfect, so we just waiting for the followup training from KM which comes a couple of months after the install to find out how we can get this 300gsm to print better. KM have an answer for everything and a "Workaround". Nothing has stopped us dead in the water yet with the C1085.