Zofran is a miracle drug, it is literally the only thing that has had any effect whatsoever on my morning sickness. Maxolon did nothing, and all those morning sickness remedies out there are an absolute joke (eat foods with ginger in them; eat a dry cracker before getting out of bed, etc etc), when you have morning sickness this severe. Nothing else works. It should definitely be subsidised, because to have morning sickness as bad (and much worse!) as I have endured, all day, every day, it is simply impossible to function as a normal human being.
That said, it doesn't always work. I took one of my wafers today, and I have been sick 4 times already today. I took it after my first spew, and it had a good 45 minutes to work it's way into my system before I was sick again (it's only meant to need under 30 minutes). Most of the time it has worked for me though, and throughout my pregnancy, it has saved me literally weeks of being curled up in the fetal position on the floor, unable to even move except to be sick.
A tip - you can usually get it cheaper if you are admitted to a public hospital for m/s, and you can get a script from the treating doctor. The script must be filled at the hospital pharmacy though. But there's only so many times they will do it. I managed to get 2 x 12 blister packs of the 4mg wafers for around $34 each pack, which is a substancial saving considering the cheapest price I could find when I contacted a range of normal chemists was around $10 a wafer, which lasts up to 8 hours.