I have some very good news for everybody:
The US indices (for example SPY) do use the European Style, and are IMO sufficient for this system.
And: indices usually don't gap much, unlike stocks do. This is of course very good for this system.
Then, this system can indeed be applied at the US exchanges alone...
Since indices are not that much volatile, it follows that the options premium (ie. the credit for the options seller) is somewhat lower, but it still is sufficient, IMO.
I'll do some calcs...
Update:
With current SPY levels only a PnL of +40.1% p.a. is possible.
I'll try to find better ones...
Here are the details for SPY (assuming Put premium equal Call premium, though in reality they differ slightly):
Stock: SPY LastPrice at Close today=209.24
CallOption: SPY160520C00209000 2016-May-20 Strike=209 Call=2.94
(-->
http://finance.yahoo.com/q/op?s=SPY&date=1463702400 )
Then the PnL would be (at 2:1 margin use):
sys14:
Contracts=1 (1 short Call)
CreditRcvd=1 * 2.94 * 100 = 294
StockPos=209.24 * 100 = 20924
UserPart=20924 / 2 - 294 / 2 = 10315 (the basis for the PnL calcs)
MonthlyPnL = 294 / 10315 * 100 = 2.85%
AnnualPnL = ((1 + 2.85/100)^12 - 1) * 100 = 40.1%
sys15 (the combo-system):
Contracts=2 (1 short Call and 1 short Put)
CreditRcvd=2 * 2.94 * 100 = 588
StockPos=209.24 * 100 = 20924
UserPart=20924 / 2 - 588 / 2 = 10168 (the basis for the PnL calcs)
MonthlyPnL = 588 / 10168 * 100 = 5.782848%
AnnualPnL = ((1 + 5.782848/100)^12 - 1) * 100 = 96.32%
As said in the previous posting: since the requirement for European Style options is no more necessary,
we now can use these systems also with any stock options. Then there could be maybe some better ones
than the above SPY index.
I'll soon do a "gap analysis" of all the US stocks...