I have never micd it up, but I had the unfortunate displeasure of playing one.
Honestly, the hate is justified. They don't sound awful for playing by yourself, but they have tons (too much gain) on the high-gain channels and then too little gain on mid-gain channels to get a nice, defined, modern metal guitar tone.
Also, absolutely no mids, tons of bass, basically they are made to appeal to the beginner who doesn't know any better about guitar tone. Obviously, scooped mids and tons of bass may sound good in a room by yourself (to untrained ears) but in a mix it will all fall apart.
Ultimately, you can honestly use anything these days and get good tones, but the Spider does not make it easier to get good guitar tones at all when compared to a 5150 + TS with Mesa 4x12...and ease of use and ability to get to a final product ASAP is all that matters today. For recording, expect heavy EQ if you want a tone that doesn't sound mediocre.
