ER skimmers are top notch.... the ASM is the toyota of Lexus....
you can do a lot of things to the G series skimmers that i probably would no attempt with a ER. a little bit of tinkering you can make the ASM a beast.
bore out the venturi, meshmod the impeller, gate valve, maybe a homemade neck extension...
they are good skimmers for the money. I have used them all. I still like ER. but if the budget doesnt allow.... the ASM is a good second choice....