I have had a Bounty Dble cab 2wd for about 5 years, 2001 model.
Bought it with 214,000 on the clock. The dealer service book had every single stamp on the history. I have done a head in the last 6 months, because it was showing all of the above symtoms
Talked to a mate and he said to buget on a head every 160,000 k's. I got a "pirate" chinese head and with machining and new valves, head studs (torque yeld), and gasket set for about $1400.
Did it all myself. Have done the cam belt myself a few times, got this down to under half an hour
It just turned over 333,000 k's last week and runs like a clock. No drive train issues at all
They are ok in my book. Just the head issue to deal with
Here's how the boar looked at 315 km's.
You can see the water marks. Took 2 years of adding coolant occasionally before it became an issue, (peeled through No 3 glow plugs tho).
Cheers, Hope this helps.