Zeppo,
You seem a little out of touch with regulation.
Since MiFID there is no 'intermediate' cateogry. All clients are retail, professional or eligible counterparty. The vast majority of CFD traders are classified retail. This means that -unless they have opted to transfer title to their funds, all funds have to be segregated, so your point about commingled funds is no longer correct.
Secondly, I'm not sure why you think that turbo pricing is more transparent than CFDs. There is only one market maker - SG- and they're not transferrable. Granted, the fact that they're listed means that your counterparty risk is to the exchange not a dodgy broker, but the execution risk is identical - you're reliant on the goodwill of one market maker.
Frankly, DMA CFDs seem more transparent to me; you're using the CFD provider as a broker not market maker
You're right about the regulation bit - I just checked IG Markets, and they do segregate their clients money; they didn't do that before, but they are MiFID compliants.
Other than that, their conditions are pretty much the same as their spread betting counterpart; and they state clearly that they can widen their spreads as they see fit.
In short, with CFDs you'll get different prices, just as with FOREX "brokers" and spreadbetting firms, on the underlying, and with different providers.
With Turbos, you get one market maker, but at least they don't make up their prices.
For me, it is all bets, whichever way it is put.
What would the difference be if, say, tomorrow the Treasury decides to tax spreadbets? Or not to tax CFDs? There would be little difference between each other, wouldn't it?
Anyone would like to comment on this?
Eduardo.