Your "go to" lps for system evaluation

My apologies. I failed to do a search first and even then it should have been in another category.

Sorry guys. You are right. My inquisitiveness got the best of me. As to my mention of Holly Cole, "Romantically Helpless", I wasn't trying to use it as a wedge to distract this thread. I find it to be a very good LP. The first two songs on side A are my favorites, her rendition of Paul Simon's "One Trick Pony" and the title track. 
I will behave myself now. Don't want to be on Santa's naughty list.

@ valinar

It has been a few years, but one distinct thing I remember is the improvement in tonal and timber accuracy of the piano after replacing the sub-platter and belt.
My memory is not that good to be able to recall the exact type of improvements that resulted in changing the counter weight.  I will say, without leading you astray that I believe you will hear finer detail due to greater accuracy in tracking of vertical modulation.

I don't want to solicit a product here, but in addition to the mods we have discussed, one of the most obvious improvements that came about on my turn table source was replacing the Black Cube SE  PWR Box fuse with a Synergistic Research Black fuse.  I have a PC of there's now powering my CDP.  One of these day I plan to swap it out to see/hear what gains are made.

Recently I purchased a Lyra Delose. I set up tangent and overhang alignment using the Rega supplied gauge.
From conversation and reading, I understand vast improvements are heard by using a Mint or Wally Tractor gauge. So the research and pursuit of one of those gauges is in progress.

Rather than discuss off topic here, if you want to talk further on the subject, you are welcome to use the PM message feature of this site to contact me.  

Being clinically unable to do "critical listening" I just play my favorite albums: Pink Floyd or Dead Can Dance to see if the end result puts me "in the mood". 
Solo violin was used by my local dealer to demonstrate that the "mods" of an aftermarket mat and platter rim "killed" my Sondek. So now I have 24 Caprices by Itzhak Perlman as a test LP, but No, I do not use it for my system evaluation.