My number
I did my first solo in around 10 hours. There again I flew twice a weekend and I was on the end of some great flying weekends with no breaks due to wx.
I think the question is relevant though. Given you are paying such a large amount of cash for a PPL it's good to have a yard stick as to how far you are against money and time spent.
I got my PPL on 45 hours, so using a sample size of 1 you can suggest solo at 10, complete at 45.
This is not due to some incredible aptitude on my part. It was due to having an incredible instructor, now I've been flying for a year and a half, I can look back and understand how lucky I was to walk into such a well run flight school. Especially when you read on here about others ending up not so well off.
Also I had no commitments, and the money to fly every weekend, plus I took a couple of weeks off work and worked 7 days a week 9:00->17:00 on the flying. Which again helped the solo'ing and completion.
I guess I'm just trying to get at, as others did, your natural ability doesn't have as large an impact on your solo time \ completion time as a whole bunch of other factors in your control.