High end stereo preamps? Worth it?

You will see a number of people singing the praises of the Don Sachs preamp.   They are hand made, custom built, dressed up versions of the VTA SP14 kit.  The Don Sachs preamp will run you about $2500.  The base SP14 kit will run you $1090.  Fully tested and assembled, it will run you $1490.  There are options for better caps, remote control, attenuators, etc, all at a reasonable price more.  The SP14 is very plain Jane if that's an issue for you.  

90% of those who buy the SP14 will get the kit version.  Not all that hard to build.  Excellent instructions and building it will result in you being much more involved in the sound.  The SP14 is every bit as good as any of the other preamps mentioned here - Audio Research, Prima Luna, Manley, Cary Audio, etc.

Depends?  Sure ,   High end preamp would be better than a cheapie .                   Better than no preamp ? Depends on the source and number of sources.  Many sources would benefit from preamp.    One terrific  source with built in volume control , in my opinion is better than adding a high end preamp.   I tried a few preamps with my Pass Labs Xa 100.8 and MSB Analog DAC.  Always preferred no preamp.  Note I tried Pass Labs XP 22 and Audio
Research Ref 6.  I would call these high end preamps.  Every preamp I tried added coloration , diminished tops and bass and muddied transparency.   I could not blame the additional power cable and interconnect because it was the same as the first interconnect and all the other power cables.  Tried in my system back to back settling  the run in preamp and cable in my system .   Maybe because the MSB volume control module module is so darn good. 

I agree with hide45, the Quicksilver linestage is a terrific value. I have both versions of the Quicksilver preamps, the remote and the non remote. They are both great, the non remote is probably a little better in imaging, although there is very new version of the remote that apparently is as good as the non remote. Very reliable as well

@alfa100

my experience exactly with Antelope Zodiac Platinum +10m. If the phono preamp has enough gain even analogue sounds better through the Zodiac than the preamp.

I have a audio research ref 5 preamp on one system and a boulder 810 on another.   I couldn’t see living without them.   I’m using the LUMIN family of streamer/DACs.   
I recently purchased a benchmark lA4 to match up with a first watt SIT 3, and I find the benchmark to be quite remarkable regardless of its relatively low cost.