I suspect the low rate of return may be because there are many Technician
class operators on the band and as such do not have QSL cards like the HF
ops. But gee one can make their own with a computer and an ink jet printer
http://www.qsl.net/wa7s/
I use the Kit from this guy, works well easy to do and you print em as you
go.
http://www.hamstuff.com/