Spark is head and shoulders above the U530 and anything else out there at the moment, and I thought that was extremely good back when it came out. Spark reacts so much like a real amp, very touch and dynamic sensitive and sounds good right out of the box. I love the pre-EQ'd cabs, saves me so much time. Can't wait for the next product (I think it's either a Mesa or a 5150!) - I hope it's neural network based too as your competition will probably be Helix Native from Line 6 at that point (which definitely is neural).