Don't forget Weighted MAs. I played around with 21 & 55 on 1min for a while. OK when the market was trending. I think it's one of those things you look at from time to time.
Like all indicators, it's OK if you need something to "hold your hand" when you're in a trade.
I've used them for confirmation. ie. I wouldn't enter against the MA.
To be honest, I'm not keen on any indicators.
As per Oatman..I also am not keen on any indicators..this may not be specific enough to help you..but do you wish to try and think about strategies from a different slant..that is do you think any strategy that is highly transparent will make consistent profits ? Xovers in the main fall into that category...
everyone has tried moving averages of some sort. I once had a moving average optimiser and spent hours everyday finding a good combinition, sometimes using 7 or 8 moving averages at once, othertimes just using one.
markets change so often so you can't keep using the same MA combination for long
I successfully day trade the Dow using only SMA's and achieve an average profit of 50+ points per day. It may not be the best strategy, but it is simple to understand and works for me.
Ultimately success is achieved by what works for you as an individual, not what does or doesn't work for others.