Experience with the Sont DSLR's?

[Allegan Archer]

Anyone have any experience with the Sony DSLR line?

I have a Alpha A100 and it takes better pictures than I do but any ISO higher than 400 (and even 400) its gets horribly grainy.  Does anyone know if the 300 line is any better?

Think time maybe coming for a new camera and was hoping to stay with Sony since I have a handful of accessories already.  But if they are as bad with the higher ISO's I may just jump ship to Canon or Nikon.

Thanks in advance for your help.