I'd take a contrary view here. What you've got with the Bizango is a very modern bike with modern thinking. Some may call that fashion, there may be some truth in that or there may not. Once 29er geometry was a compromise and flawed in some sizes, those days are past. The only compromise these days is as you have to fit it to a smaller rider, then you need to look carefully at the bikes geometry as some manufacturers don't do small sizes because it requires bending tubes and integrating headsets.
The Bizango is bang on the money. It's longer wheelbase is shortened by curving the seat tube near the bottom bracket, keeping the rear stays a sensible length. The bars and stem are high and short and the bars wide, this is pretty much the trend for current mtn bikes. Contrast that with a 90's bike such as I've come from, which has narrower bars, a lower front end and a longer stem. The difference is night and day in handling and my 29er is far better off road.
I think the Bizango looks a sorted bike. Yes you may need to make changes to the bar and stem. Yes, it's very upright for the road but that comes into it's own off-road. I reckon it fits in terms of height, other manufacturers make a longer top tube but as you only seem to have access to Halfords, there's no point in suggesting them and as I say I think you could experiment with the stem and bars if you find it doesn't quite suit.
I went through this process very recently when I picked and built my own bike a Kinesis Maxlight ff29, the build of which is on here. I spent a lot of time reading about handling characteristics of 29ers and then rode some. Buying a 29er came about from my wife choosing one and me having a go and being impressed.
29ers seem to evoke a lot of emotion and the camps divide. Like any bike it's about picking one you think will suit what you do and one that fits, which we've covered and also dispelling the myths that seem to surround them. I say again, all of the geometry issues that affected handling of 29ers are sorted now, you need have no fears on that. Just decide if it's the bike you want.
Incidentally my own long low 26er is being turned into a touring bike. I wouldn't consider doing that with the FF29, it's a different bike and this is why many of us have more than one bike for different purposes.
