DEATHCLAIMER27

Magnetometric - this is to find professional sites (archaeology and salvaging sites).
Gravimetric - this is to find asteroid belt sites.
Radar - this is to find hacking sites.
Ladar - this is to find gas cloud-related sites
Unknown - this has a chance to find a complex with a chance to escalate.

Quest - 4AU, 4000 seconds, 2.088 AU
Pursuit - 2AU, 2000 seconds, 6,250,000km
Comb - 1AU, 1000 seconds, 125,000km
Sift - .5AU, 500 seconds, 2500km

Class 1 and 2 systems can be soloed.
Class 3 you want some friends with RR.
Class 4 you want lots of friends with RR.
Class 5 you definitely want lots of friends with RR and probably a capital.
Class 6 you definitely want a capital or two and lots of friends with RR.

Perimeter sites are generally Low difficulty.
Frontier sites are generally Medium difficulty.
Core sites are generally High difficulty.