IG - don't get me wrong - there are some others much, much worse. Some other SB companies have tens or even hundreds of points discrepancy, invented prices, connection problems, massive slippages, suspended dealing etc. So in the greater scheme of things they are quite reasonable.
IMO If one is unfortunate of being played on a regular basis, they stand no chance whatsoever.
That's interesting. I must say that I haven't had any particular problems, although I must stress I'm only talking about their "futures". Perhaps that is not worth monkeying around with because the real prices are what they are being on a proper exchange. Forex might well be very different.
I spent some time running IG's prices alongside those from my futures broker and there was effectively no appreciable difference (again, assuming you're not trying to do very quick, short trades, which nobody in their right mind does with a bucket shop anyway).
I do get slippage on NQ from time to time, although I get it when trading in the real market as well, I think that's just a function of how fast it can move. Try just trading NQ using limit orders, the best trades you'll often get partial fills if you get filled at all. I always enter with market orders, because almost always if there is some slippage it's worth it to get in. That said, my stops and targets are probably quite wide by the standards of most people that do futures intraday, so a half point slip isn't an issue for me compared to someone that's shooting for a few ticks.
I think you've been very fair to them, and I'd agree that among their peers IG are not at all bad. Again, it just comes down to the individual, how and what you trade etc.
To Doom I'd say that you need to treat it as a business, which means not becoming reliant on any one broker or bucketeer. I've tried quite a few, and have a number of accounts that I'm familiar and comfortable with, so the moment I'm not happy with someone I can dump them and resume trading elsewhere without a break.