I've seen a lot of Buicks with the plastic panel under the license plate warped from heavy zylene use. The aromatics are tough on plastics.
I dont know if there has been any long term use of it.. that i'm aware off.
I used it too before I went the alky route. At 10.00 per gallon.. after a few gallons I was done.
A DIY alky kit while not fancy will give you the xylene results with careful planning for not a whole lot of $$$. Definetely less than a 55 gallon drum. For that money and hassle, i'd do an alky kit. Opinions/bias aside.
HTH