Thanks, been using that method. I also have syringes to try, just waiting on another order of blanks from Heavens Gifts. I think I've burned up one cartridge already, lol (have to get the knack of knowing how much to fill, when to top off...these things all have their quirks). Loaned my second battery plus an RY4 cartridge out to a colleague who hasn't yet got the hang of her M601. I like the simplicity, and the flavour.