I would recommend SRA (Silent Running Audio) any day. They make isolation platforms including the type that sit on the floor/carpet to support amplifiers. Kevin Tellekamp who owns SRA apparently does military applications for submarine isolation. He translates some to the secrets into his commercial side of the business. I can say that whatever in these platforms actually works.
Back in my early days with entry-level equipment, just about any support (stand and rack included) would help improving sound quality. As I get pieces of equipment of the same caliber as your XA100.5, these gadgets becomes a hit and miss. They can help in some areas, and harm in others. I stumble into SRA some 5 years ago, took a calculated risk waiting for them to tailor-make me a platform for my Meridian 808. Needless to say ever since then, I've gotten a few more platforms/stands for other pieces of equipment. Unlike all sort of supports, SRA platform does not augment the base or treble, creating a sense of vividness at the expense of something else. The end result is simply deeper soundstage and more detail in the music fabric. The down side is that these platforms are made based on your listening room and all kinds questions they'll ask you. They are considerably more expensive that your typical amp stand. Each piece is tailor-made and you have to wait for them to make it for you personally. But the wait is definitely worth it.
