They're a fun kit to make but the refills always leak. I write a sentence with them first and then stand them on end for a while to check for leaks. If they do, I use the German made refills to replace the crappy ones that come with the kits.
It is a good quality kit other than that.
BTW, the tutti-Frutti one was made using a couple of scraps and barely had enough to round it by about a 1/32".