It's simple really. The 964 is a more comfortable car and therefore would make a better daily driver. Better A/C, Power Steering, Airbags etc... it's a no brainer which one is a better daily driver.
Just depends on what YOU value in a car.
People tell me I should sell my cab and get something a bit more modern and comfortable, but at the end of the day, I love the "rawness" and feedback I get from the pre-89's. Comes down to personal choice.
'89 911 Turbo Cab
Protomotive MAP ECU, Twin Plugged Heads, GT2-EVO CAMs, 3.3L fully finned P&C's, ARP fasteners, C2T head gaskets, Titanium Retainers, Turbo spec valves, springs & guides, 964 splash valves, GT35R BB turbo, GSF Stainless Headers, Magnaflow Exhaust, Full bay Intercooler, TiAL 46mm w/gate, TiAL 50mm BOV, Apexi AVC-R EBC, SPEC Stage3+ Clutch kit, Crane CDI Ignition