I'm assuming you're talking about Data Sites also since you mentioned encryptors. In my experience, Relic sites have been a waste of time (in highsec and lowsec). In Data sites (lowsec), I've managed to find a decent amount of isk by going for Parts Container which had encryptors (maybe around 30m per site on average?). I don't remember seeing any encryptors in material cans, but I haven't really kept a close eye on what those gave. I just know that if a cargo scan shows encryptors, I will definitely find them in parts containers.
Its not great isk, but its something newbies can do without too much training. For lowsec sites, the Hacking and Archaeology skills at 4 were sufficient. I get most hacks on the first try, if not the second. Only very rarely have I had a can explode on a 2nd fail. I do not have the hacking rigs, but I might try them later. Having the right strategy helps a lot, blindly clicking on any open dot is not a good plan for successful hacks.
The story of a master and his beloved pet.
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