1.What would happen if a dapp runs out of RAM? A: It will not deploy, or not run.
2.What was the change between Dawn 3.0 and Dawn 4.0 in terms of the RAM market? A: 1st the RAM price was fixed, then the 2nd RAM is priced by the market offer-demand decisions.
3.What are the benefits or having a market based model for RAM staking? A: Non used dApps/Unused-resources are incentivised to free up RAM.
4.What are the drawbacks of having a market based model for RAM staking? A: RAM becomes a speculative asset and developers will have now to pay market-price to have RAM to develop and test new dApps in EOS production environment.