I own a Hyundai excel for the last 15 yrs and am more than satisfied with the performance, comfort, drive and even maintanance costs. I have travelled all over Pakistan on this car from karachi to quetta, peshawar to karachi, peshawar to quetta and even north and south waziristans, hangu, parachinar etc without a single issue ever.
As far parts availability is concerned, NO problem at all. All korean vehicles are replicas of Japanese vehicles and this one is the same as Mitsubishi Lancer. So all engine and suspension parts are perfect fit without any alteration / modification. For example I changed the gear box to 5 speed ( originally it is 4 speed) with a kabli one 12 yrs back and it is still running perfect. CNG perfromance is outstanding, it gives me 110-130 in city and 180 on highways on a 8 kg cylider (55 ltr capacity). On petrol it still gives me 12-13 per liter on long routes (not checked in local since long). AC is just like the one in any big car. I own a 2003 corolla too (Alhamd-o-Lillah) and cant spot a differnce in performance between the two. Rather I must say I have found corolla to be more expensive in terms of parts.
YES, there may be a problem with body parts but Alhamd-o-Lillah never met any accident so not sure about that. Though I have seen a lot of parts in Peshawar, Pindi, Lahore, Quetta and Karachi second hand parts markets.
So, I would strongly support Hyundai excel PROVIDED you get one that is real clean, never abused, unaltered and not modified car. It may be hard to find one such but not impossible.