What winning % should I expect at heads-up SNG??

[Rubber Soul]

I posted this in the heads-up section but few there had any info on the subject, and one suggested the people here could help, so I'll try again:

I have just started playing heads-up SNG's after I beat a friend of mine in three straight heads-up matches (he plays far higher stakes then me and my beating him inspired me to play more)...

I am curious what kind of win percentage is "standard" at $10 heads-up no limit hold-em sng's and higher...

As far as my background (if that makes any difference) I have been a winning online player at low stakes nl hold-em (up to .25/.50). I have had 13 straight winning months in a combination of 6 max and full table ring games at various online sites. I have not moved up to higher limits because the $600-$900 a month I make at the low stakes is very much needed as a supplement to my income. I only play a few (say 4 or 5) multi-table tournaments a month and I have a pretty solid record at them (I usually play tournaments with buy-ins between $10-$30) and I have had two big $1,200+ cashes as well as several other small cashes...

So far I have played about 50 of these $10 heads-up matches and I have a 70% win percentage which seems really high... Should I now move up to the $20 games or do I need a bigger sample size?

At full ring games and tournaments I am a very tight aggressive player, but at these heads-up matches I am super aggressive. I raise the pot 80% of the time from the button and often bluff at big pots when I sense weakness...

So, am I just on a hot streak, when should I move up, will my hyper aggressive style work at higher levels? So far I just feel like I am in full control of virtually every match I have been in, and only general variance (other guy getting great cards) are the reasons I have lost those 30% of the time... There really has only been one or two opponents that I have played that I felt were as good as me or better...

So, what is a standard win rate for $10 heads-up matches and higher???

Thanks in advance for any posts...

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