There are 2 distinct bottlings of this.    The labels will be identified by "Louisville" or "Frankfort." 

The Louisville bottling was distilled by the Stitzel Weller distillery making it the most sought after and collectible.  That was likely bottled by Diageo (pre 1998) prior to Buffalo Trace (BT) acquiring the brand. 

After BT acquired the brand they labeled it with Frankfort.  There are 3 different iterations with the Frankfurt label and can be identified by the bottle shape and the wrapper covering the cork.

Frankfort:

1) A square bottle with cut corners and black top wrapper stating "Bourbon Heritage Collection." 

2) A square bottle with round corners and black top wrapper stating "Bourbon Heritage Collection."

3) A square bottle with round corners and yellow top wrapper.  This wrapper does NOT state "Heritage collection" as BT dropped the heritage collection line.  This is probably the last iteration of the Weller Centennial

There will likely be differences in taste due to year of distillation and to the nature of the small batches.

Version 1:

Orange peel nose, not enough oomph.  Flavor fades too quick.  B-

Version 2:

N: Faint at first, but opens up with some maple sugar. Orange peel.

P: Oily with lots of tobacco, kinda creamy.

F: Hints of black licorice.

Kinda odd tasting, but good. B/B+

Pure sweet Bourbon on the nose.  The palate starts sweet with acidic/citric notes typical of a wheater, then a rush of oak and layers of fruit and spice.  There is a long, sweet finish.

This is a superbly balanced and delicious wheater.  Great stuff.

n: Vanilla and ashes

p: Cream soda and woody cherry.

Solid, not stunning  B

separate note, gold top (not sure if it is the same as above

n: Caramel and taffy

p:  cedar and bitters,  C+

Frankfort: vanilla sweetness with some spicy rye notes and citrus.  B-

L-ville: much of the same above but has more oiliness and wheat character and nutiness. B

N: Sharp-ish, some prickle on the nose, slightly solvent. After a moment there's orange notes, slight molasses. Creamy with light vanilla. 

P: Smooth, good wood influence. Sweetening, moderate warmth. Some vanilla, light apple, and pepper.

F: Slightly dry, fruity and a hint of orange.

Pretty decent.  

n: rich creamy toffee, brown sugar mixed with butter; excellent nose. Browned pie crust and baked apple.

t: cherry cola, tobacco leaf, and a bit of molasses. Orange wax in the middle. Very enjoyable with full flavour but nothing gets hot. Finish is a bit on the short side with pepper.

[Frankfort version 2, B (almost B+)]