Great sounding WLP LPs.

No contest... Carly Simon "No Secrets".
Iron Butterfly "Metamorphosis"
what is WLP?
I asked myself the same thing. I am assuming that WLP stands for "White Label Promo", but I really don't see what the OP is asking? Most records had a release as WLP for a small, first batch to the industry.
If it is White Label Promo, then OK.
I have a few promos which have some unique feature.
I like the QuiexII promos I own the best.
Then i also have a few of the white lable variety, and a few colored vinyl types. (where only the promo had a unique colored vinyl)
As for if they are better, not. Exception being the QuiexII.
The one advantage of old promos is they most likely were played less. Having been in some DJs collection for many years, just sitting there.
I have several WLP's and they can be fantastic, however many of them have been played extensively and are noisey, though even those can be better than a quieter regular pressing. A few titles that come to mind are Born to Run, Darkness on the edge of Town, Billy Joel Turnstiles (excellent).
It's (funny) that my response to "Tbromgard" several days ago, was never posted. Oh well, it's not the first time. I'm kind of the persuasion of Tom Port @ Better records. I have heard for myself, the difference between pressings of the same lp. This is why I (asked) others of their RECOMMENDATIONS for WLP. Knowing that these arer sometimes tipped up in balance, there are some that exceed normal pressings.

Ther, I did it, I explained myself!
A promo is the first stamp pressing sent out to radio stations.Everyone one I have sounds better than standard press.They are expensive and rare in mint condition.One of my best sounding promo's is Zappa Sheik Yerbouti,maybe the finest sounding guitar recording in my whole collection.Also Joe's Garage promo of guitar solo Watermellon in easter hay,awesome.
Thanks, Playpen!
The two LPs I mentioned above sound great each time I play them
I have been checking out the sound of many WLP (mainly classic rock and prog) through the years - it seems WLP is US pressings only...examples of awesome sounding WLP in my experience is Free - same (1970 2nd record), Highway and At Last. Alice Cooper early recordings (BDB, Schools Out, Muscle Of Love and Love It to death) sounds better on WLP than any other I've heard...I also like the sound of WLP Cat Stevens Tea Tillerman for general I feel you can't go wrong with late 60s/early 70s Warner Bros (original press - many of the big numbers were reissued many times with WLP label variations/later presses) WLP...there are a few WLP I've encountered that sounds much inferior, though - ELP 'welcome back' and Yes 'Relayer' comes to mind (banded for radio, both...)...
Have found WLP's to be excellent but the biggest difference I've heard is Rick Wakeman's "The Six Wives of Henry the Eighth". I have both a regular 1st pressing and a Quadraphonic Promo and the Quad promo beats the pants off the regular issue.