I've been using a fixed pressure for many years, but have just had a prescription change to an auto-range.
While making the setup changes yesterday evening, I was keeping a lot of the info I've read on this forum in mind.
One of the suggestions I usually see is "raise your minimum pressure". I noticed a setting in the PR Dreamstation that programs the machine to use a starting point of the previous session's 90% pressure. The menu lets you enable/disable this feature.
If this is set, then the machine is automatically raising the minimum, isn't it?
Opti-Start is a new feature on the Dreamstation, and it does act to start machine at the 90% pressure of the previous 30 hours of use. In a normal CPAP titration, the sleep lab targets te 90% pressure to minimize OSA as the recommended prescription. With Opti-Start this is continuously recalculated, and will keep your starting pressure higher than the minimum pressure set on the machine. This is a great improvement over issuing a machine set wide-open a 4-20 pressure, and allows those setting a chance to actually work. The Philips machines are not very fast to respond to obstructive apnea, and a higher starting pressure can help get the machine closer to that optimum therapeutic pressure. Opti-Start is a good way to get that done, or you can do it manually by raising the minimum APAP pressure.
If you enjoy and tolerate lower pressures, there is nothing wrong with setting minimum pressure at 1-2 cm below the 90% pressure without Opti-Start. It's really a matter of choice. I think Opti-start is a good idea, especially for people that are not savy about optimizing machine settings.