Ya,prices on the famed preamps of yesterday are thru the roof right now..I own most of them. While I'll say they do cost more,some of the prices I see on them now is just plain absurd.Like everything else I guess..if you want modern preamps built in current production, you're lookin at the synergy stuff, black widow preamp, and maybe a few others.
Kartakou Colossus preamp is basically a 5150 and 5150 II preamp. They sound great but the new version was a bit buggy imho. Sounded amazing but it defaulted to the clean channel and you had to flip it on and off twice to get it to power up. Small annoyances but annoyances all the same. The version before the current one didnt have any of these quirks. Also he is in Belarus so when you order it takes over a month to arrive. I imagine its even worse in these climate.
The KSR Ceres is fantastic. I dont think one of these are any less than owning a KSR amp. Especially when paired with the PA50 its as good as having a KSR amp. I ended up selling my Ceres and PA50 to get an Ares just because I prefer a head but if I was playing shows this would be a no brainer.