I don't fully understand your point here. Do you, by this example, assume that DMA is less costly when it comes to short term trading? As I see it, this is not always the case. Of course, it depends on the instrument you are trading. I would, in fact, say that a very short term trade on the DMA is more expensive, compared to the narrowest spread traded on equivalent instrument on SB. On top of that, for DMA you have to pay tax as well. The actual cost for the spread is the same whether they are short term, or have a longer time frame. However, I do get your point that the spread does not play as important a role, on a trade with a longer average tick per trade. Please fill me in if I missed out on something important in your example.minx said:Ok so it depends on the products you trade and who you trade with but my commissions on my most heavily traded product are around 1/15th - 1/20th of a tick so its a total non-event. Afaik, IB are pretty good for retail commissions? If you are trading a lot of US commodities then your commission rates will soar but the bottom line is how many ticks are you making per average trade, if its high then SB, if not then DMA.
EG: Average Ticks Per Trade= 4, DMA spread=1, SB Spread=3. After the spread your average ticks per trade on DMA =3 and SB=1 so already you are better off with DMA (inc commissions) and paying Gordon his blood money. If your average ticks per trade is 20 then SB is much better as you'll have +17 ticks Vs +11.4 after-tax DMA.