This subject matter/question could go in two areas on this forum, but I chose to place it here  because of the Shaver unit.  The wood I have been putting ion my 250 is from when I cut down 6-7 red oak trees 5 years ago.  This wood was cut in 18-24" lengths and split because AT the time it was just going to be used in my wood burning fireplace in the lower level.
So now I "know" from others telling me this that I should NOT block the chimney in the rear of the unit...another no brainer.  I have been loading the wood and placing it more towards the door and front sides.  Do I dare go further back when piling wood in there?
I do not stack it up to the top...I do leave about 3-4" from the top of the firebox.
Next question, I'm going to be ordering up wood come either early January or mid January.  I think it will be coming in 8' lengths.  Given that this Shaver 250 is 54" deep on the inside, how long should I make the wood when I cut it down to size? 2'? 3'? 4'?   And do I split it or leave it whole?  It will be 2 year seasoned hardwood.  
I'm sure I'll think of another couple questions regarding this as the day goes on, and I will come back and add to this post if that happens.
As usual, I thank you in advance.
Lugnut
aka: jerry