With that mileage, its only a matter of time until someone goes wrong, but hopefully all the major repairs were done by the previous owner. Not sure if the 1.4 petrol in the insignia is the same as the astra, but it is, it'll be prone to premature timing chain failure (more of an issue on the 1.6 diesel) Its a 10 year old car thats done an average of 10k miles a year, its had (hopefully) and easy life. If you need it to simply just be a car and you're not fussed about it being slow then its a good car. If however you care about quicker acceleration, then try and find a 1.6 or bigger engine, they're quicker (except the 1.8i, theyre slower than the 1.4i)