Have you noticed how quick people are to blame the spirits in Goetia when things go badly? I've never seen any system so quick to get booted to the curb in spite of previous successes. Magicians can have years of good results with a spirit, but if they have one bad experience, all the spirits of the system are bad bad bad.
There are so many assumptions and prejudices surrounding these spirits that the skills required to use them effectively, consistently may never be gained, documented, and disseminated to the occult community. It's annoying as hell. If people shelved Angelic Magic, Planetary Magic, or even your average Pagan conjurations of Hekate every time they had a ritual provide results they didn't like, no one would do any magic at all.
Jake Stratton-Kent has said for years that the line between angels and demons is thin indeed. When you look at the gnostic texts, as he points out recently on the Solomonic yahoo group, it's not only the alleged "angels" that are demonized, but God himself. Yet magicians are perfectly fine working with the Angels. He points out that Cassiel, Archangel of Saturn, is listed as a demon in Barrett's The Magus, and that Uriel and various "angels" associated with Venus also have a "Dubious history."
I think the problem is that doing magic is simple, but learning to do it well takes time, practice, patience, research, and perseverance. A quickness to retreat from the system at the first sign of trouble is damaging to the magical art in general, and is a disservice to magicians of the future. The prejudice around the Lem's Spirits is largely unwarranted. Sure, they may burn your house down if you're stupid enough to say, "Do whatever it takes to get me this money, just don't hurt anyone," but stupid gets what stupid puts out. It's a Spir'tual Law.
I believe magicians have been lulled into a deep sleep when it comes to the Goetia. The idea that they're "demons" has left people with a blind spot. There's a great deal of negative expectation around it, but little actual evidence to support it. "I used Goetia, and it didn't stay forever exactly as I wanted it when things changed," or "I used Goetia for years, and then I had a bad experience so they're all evil and bad" are pretty standard. I don't get how people can just toss out their success with the system so easily.
The really funny part though? When things go well with Goetia, it's because the magicians are following the grimoire's instructions properly, or are psychically shielded, or somehow appropriately initiated, or otherwise prepared the way a good magician should be, but if things go badly, the spirits themselves are somehow corrupt, kick you when you're down, or are "corrosive."
But not everyone will agree with me, or Jake. Hell, I barely agree with Jake on some things, even though our theologies are nearly identical. Except for that whole "Jesus" thing. I know that Jason Miller is nearly correct when he says, "you would be hard pressed to find a magician that thought that you would have just as much problem with an Archangel as with a Sub Lunary Spirit." I say "nearly" because I only have to go to the mirror to find a magician who thinks this is true, and it's based on hard-won experience. I trust that mirror guy, he's seen some shit in his time.
Objectively speaking, I've had at least as many, if not more positive results that I was happy with after Working the so-called demons as I've had with alleged Angels. I've been disappointed more with the Angels, but mostly because when I want something badly enough to do magic about it, I want the results like fucking yesterday, man! Not in a couple of weeks.
Anyway, the whole "Angels are good, Demons are baaaaaa-aaaaad" bullshit has to come to an end. Wake up, magicians! See the systems without the "demonic" filters over your eyes! Scrub that sleep-crusted snot from your eyeballs and take a good, clean, honest look at Goetia. It ain't so bad.