Digital BW, The Print

I have a slightly off-topic question but this group has been so helpful with all my 
other questions that I would appreciate any views from here.  I currently use 2 camera 
systems - the Contax 645 and the Canon 1N and have relatively recently stepped into 
the world of digital printing.  At the moment I have a relatively cheap scanner, the 
Epson 2450 Photo.  I have not been that impressed with the sharpness/focus of the 
scans and while they have been "ok" for my recent learning curve I can't believe that 
this is anywhere near the state of the art.  I have learnt quite a lot about sharpening 
and have been using Photokit Sharpener by Pixel Genius for a few weeks now.  
However, I still don't think the raw scans are up to scratch.  For example, I have also 
used a Phase H10 digital back in a studio setting and seen how crisp and detailed the 
images are that can be produced from a good digital capture source.

So my question now is should I upgrade my scanner to, say, a Nikon 8000 or should I 
find an interim solution (such as outsourcing the scans to a lab) and save for a digital 
capture source - for example, the 1Ds.  The Nikon 8000 costs $2,500 vs  the 1Ds at 
$8000 but can a scanner get close to a high end digital camera these days?  Or will I 
find that if I buy a Nikon 8000 it will be worth little used in a year's time and I will 
wish I had applied the money to the more expensive option in the first place, albeit 
that it might take longer to obtain?

As for digital 645, all except the newest top-of-the-line and stratosphere priced 645 
backs have a sensor size equal to full frame 35mm.  Eg the H10 has an 11 megapixel 
CCD chip with an imaging area of 36.9x24.6.  The 1Ds has about the same pixel/
image size stats yet costs about 1/3 as much.  Why does anyone not needing 22 
megapixel full frame 645 buy a 645 back when they can use the 1Ds (and even 
PhaseOne's software, CaptureOne DSLR) ?

Any thoughts would be appreciated...

Cheers

Steve