No, I’m saying that in normal scan you will boost up to top drift speed, your SCM; then cut your engines and drift uncoupled for as long as it takes. SCM sets that limit, so that’s the speed to compare. This also means you can neglect IR in comparisons since you have almost none when your engines are off. The Peregrine is drifting at what? 287 was it? So it is superior to all other S1 scouts.
We can’t compare this against S2 scouts because we don’t know the S1 and S2 radii. It’s quite possible that even moving 30% slower, the Terrapin scans faster because scan goes with r^2 whereas it is only linear with speed. So if a Perragrine is 30% faster but 20% smaller radius, it will be outperformed by the Terrapine.
That said, the Terrapine cannot outrun a Vanduul Blade, Glaive, etc., so if the scan difference is not too great, the Perragrine could be the better choice.
S3 scan ships generally cannot be used for stealth recon despite no IR, because Vanduul cap ships will be actively pinging all the time. The exception may be the Zeus if it’s wearing Void Armor. I’m personally excited to see where the Zeus fits. It sits on such a flat plane that holding a Vanduul ping source abeam (to your edge) could make the Zeus EX into a monster scan platform.
In Star Wars Combine, we systematically scanned entire systems as a team, by sending scouts out to scan specific parallel sets of coordinates and inputting that data in a shared Google doc, which generated a scan map. This was all 2D. 3D will be much more laborious. I can tell you from much experience, you definitely want to use fast scanning ships rather than what’s handy. Scanning a full system could take several players several days and you don’t want to do this inefficiently. However, you also don’t want your scouts caught because you then could lose them, and even with dopey AI, you should expect to lose the element of surprise. That’s key if you’re scanning for torpedo targets.
In The Wraiths, we had adequate discipline that scouts knew to report significant finds like planets (in our case could be wormholes) but did not investigate these themselves. That should be left to another team comprised very differently than scouts. It’s important to do this or you never scan the entire system with a find, and many systems will have more than one find. So scouting requires players stay on task. In a Peregrine or Terrapin you can drift right by an actively pinging Vanduul at just a dozen kilometers, and should plan to do so. To get players to do this there needs to be significant reward. So setting up cooperative scan is actually somewhat involved.