Digital BW, The Print

I am currently saving for an Epson 4800. I can probably make do with a
13" printer but I have been pointing toward the 4800 for two reasons:

1) more precise construction = better prints (maybe) and 
2) lower ink costs. 

With respect to ink costs, I would guess that I'll print 100-150
prints per month at around 11x14 or and perhaps 20-25 at 16x20. I'm
not sure whether that makes the savings for 110 or 220ml worth it.
And, I don't really know whether the more precise construction of the
printer will make a noticeable difference in print quality. 

I'd love to have comments from users of either the 2400 or the 4800 or
both. 

Thanks,

--Gib