Digital BW, The Print

I'm looking for a recommendation for a high quality smooth white matte 
paper (in sheets not rolls). It must be white and not a warm or natural 
white. It should be smooth and not have a texture. And be matte without 
any sheen. I'd also like it to have a good archival rating (although I 
accept that to be bright white it will contain some optical 
brightners). 

I use Premier Matte (dual sided) 210gsm on my 2200 with Ultrachrome 
inkset as an inexpensive paper for testing and get good results with 
that. Their Fine Art paper 270gsm is too warm (similar to Epson 
UltraSmooth fine art).

thanks,
Frank