Sump/Refugium Design Question

I've noticed that there are many configurations in DIY sump/refugium builds. Seen many that are designed with the sump area on one end then the refugium in the middle and the return area on the other end. I have also seen many with the sump area on one end, the return area in the middle and the refugium area on the opposite end from the sump. Is one design more benifical than the other? The reason I ask is I'm changing out my 30g sump/refugium to a 40g long refugium to accomodate the MSX skimmer I have coming.

 

I would think as long as the bubbles and water is fairly calm (or however you want it to be) by the time it gets to your refug. you'd be ok either way. Ours leaves the skimmer into a smaller area and baffles (depleting most bubbles) then over the refug. (where I have pc light where I have chaeto and frags growing) then over a slanted wall (getting rid of any remaining bubbles) and through carbon and out. Ours is 40 gallon. This keeps any sand out of the return also.