My 91 745T (238K miles) has an all metal radiator that has sprung a small leak. My entire cooling system is due to a replacement so I am putting together a list of all items to replace including hoses, water pump, belt, expansion tank and cap, heater control valve, and radiator. I already have new OE heater hoses in place.

Id like to use OE parts wherever possible and am looking at this radiator as a possible candidate, Volvo P/N 8603894

http://www.tascaparts.com/oe-volvo/8603894?search_str=8603894

I have read up on this board and several others and am a bit confused about my next steps due to the radiator and coolant options out there. My goal is to have my cooling system as bullet proof as possible so:

1. In terms of reliability and longevity, is it better to repair my current all metal radiator or buy a new one? I dont mind spending a bit more if it will mean greater reliability.
2. If I buy a new one, I assume the OE one listed above is the best choice, correct? I assume it has the plastic ends like most replacement units.
3. If I buy the OE radiator listed above, what kind of coolant I should run in it so it doesn't eat away at the internals and spring a leak prematurely?
4. Anyone know if the OE radiator listed above has the push in fan temp sensor or a screw in one? My current radiator has a threaded collar that screws over the sensor and onto the rad.
5. Is the OE heater control valve my safest bet since all control valves are made of plastic anyway?

Thanks in advance,
Jose