I honestly believe the resevoir not only makes the cooling system more robust if used correctly, it also acts as a self cleaning device for the cooling system.
FYI - I am talking about a Res tank that does NOT have the pump sumberged in it. I hate those setups.
1. It lets the small pool of coolant to "chill for a bit" before it heads off down to the pump and radiator.
2. If you keep the res tank at the top of the system it will catch all the air, and auto prime the cooling system, no sucking on hoses.. ever.
3. if you make a nice fill point for the system it will make maint of the coolant VERY easy.
if you notice the Pro/Mini and DH3 cooling design have the res tanks at the top. This is the SAME way the brake'n system in yer car works. Keep the res tank high, and make it accessable. AND KEEP THE PUMP OUT OF IT.
So thats where I stand on that
Inline cooling systems are just such a bitch to maintain and keep an eye on. You know the Koolance hose blowouts would have been avoided if they would have had a air gathering and pressure regulating res tank.
So thast my take on that