If you can afford to do so, then keep it
Its not the day to day running costs and servicing that is a big hit - its the spenditus we all suffer from. If you can promise to yourself that thats the end of the mods, then assuming the car comes back fixed and all niggles solved, spot on then its worth keeping IMO
If you have money burning a hole in your pocket and you want to treat the scoob, spend it on a trackday or driver training or a tour of Scotland or something