Thank you for the feedback and for sharing your wisdom.
I know that any experience I have had with electronic drums was powered through the PA so I had no idea how it might work or sound with a bass amp.
I am going to share your comments with him and then let him make up his own mind. The amp is in mint condition with all the owner manual, the original sells reciept and priced at $150 so if he doesn't buy it someone will.
I did suggest trying it with the drum set before buying it but for some reason he didn't seem to want to do that.

Thanks again
Dave