For parts availability, there's more for the 94 to 97/98 models as this was more popular in the local market and sold well. If you're going for the 1999 up, go for the 2.5VR V6 as against the Super Saloon if you can find one. Things to look at when you inspect units are the suspension, transmission operation (if a/t), electricals, and the engine idle.
Our 1994 VR V6 m/t can do up to 12km/L in the long drives (Manila - Baguio, Manila - Tagaytay) even with some 200kph runs on the highway. Normal city driving will be at the range of 6.5-7.5Km/L+ depending on traffic conditions and when you shift at around 2K to 2.5K rpm. It will definitely drop to 6km/L+ when the traffic gets stop-and-go, bumper to bumper bad. For parts, it's not really a problem and shops like Best Colt in Banawe and surplus shops still carry good, affordable OEM and replacement parts. If you're interested, our 1st owned '94 VR is up for sale (at the classifieds section) since it's rarely being used after we got another new car.