I started to worry about my 194k on my SR, but having known its history servicing it and compiled list of minor niggles that can be sorted I'm more confident it will last a wee while. I bought this after getting rid of an 09 corsa, because it was boring and things didn't always go right with it and didn't work out cheaper in the long run. I work next to a kwik fit and see the state of some of the new cars that go in there, and regularly chuckle passing a new(ish) car on the hard shoulder having 'issues', doesn't matter how new it is, if it aint looked after it will bite your arse. At the end of the day only you can decide, But newer isn't alway better IMO.
A gen 6 GT with 180k wouldn't put me off, I wish I knew before I bought the SR what I know now and got a GT, but I'm enjoying and looking after what I've got, just happy to be in a 6