Clearly part of the reason people participate in an IPO is to...

Clearly part of the reason people participate in an IPO is to make a quick profit when the shares are listed. So I won't be buying them on-market if say the opening price is 50c.

That would give CHM a market cap of $150m for a company with one asset that's barely into phase 1. I might be wrong - but compared to other Australian biotech shares that are way more advanced in their clinical pipeline, I think CHM would be way overvalued.

But as you mentioned, if it opens, or stays around, or even goes below 20c then I would definitely consider buying on-market.