I will always reply to QSL cards via the RSGB QSL bureau or direct to my QRZ.com address.
OQRS via www.clublog.org is a great way to get my card.
I *only* handle QSL cards for:
M0PCB, MU0PCB, MM0PCB, MW0PCB, MJ0PCB, VE3/M0PCB, M1ETJ, M0VSQ, G9V, AD5XI, VP8DNA, VP2MXI.