The first cues that George built had Black Nylon Wraps on them, in the beginning / early 1960's that is all he used and if an original Balabushka is found today with one of Georges original Nylon Wraps it is considered very Rare and worth a premium.
It appears that many of his early cue owners had him change their wraps once he started using Cortland #9 Irish Linen.
So while I personally do not like playing with one, many older cues by some high end makers especially those made in the 1960's did have Nylon Wraps, what it all come down to is that you have to know what to look for and a decision can't be made by wrap alone of even by having the Pin in the shaft and not the cues butt.
Hope this helps