I think you will get roughly the same opinion from most regarding the heater core vs BIX.......The heater core will walk ALL OVER the BIX.......
But it depends on what you are looking for......performance vs being pretty. Hose clamps would be a GOOD idea......but not those little plastic things......use HOSE CLAMPS
I personally dont care for the closed loop applications (no reservoir) but many use it with great success.