Opel's reliable? Tell me you're joking
As for this case, from the '93-'00 they were in theirs dark age. Some of the worst engines in Opel's history were produced in that time. Those cars also had a chassis prone to rust in almost no time. Gearboxes also prone to malfunctions. At say 230,000km it needs to be completely repacked or it falls apart if the 5-speed F18 gearbox is being used, the one which has R next to the first gear.
In Germany they have a saying, this is literal translation: "Germans driving Opel are the ones who can't afford a real German car, but must say they are driving one".
Good part is that the replacement parts are relatively cheap and widely available.
I drive Astra 2002. But as opposed to Vectra in case, mine has 1.7 Isuzu diesel engine since both Isuzu and Opel are parts of GM group.

Oh, this was great. At the moment my dad was still using this car, 3 days after warranty expiration, turbo broke apart on the highway. 3000 total repair costs with labor and transportation to the nearest repair shop.
3 months ago I was on trip, don't know how you Americans call it, the part which produces electricity after the engine has been started(dynamo?) broke down. 150 repair in total. They are installing both Bosch and Delco parts, but latter is a piece of junk.
Very reliable

But as I love mine because it is relatively cheap to maintain and has very low gas consumption.
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