TBH I wouldn't worry, coil packs can go on any car, BMW have had problems with them on some 3 series models, when buying used it a sometimes better not to know how the previous owner treated it, we all hope they were looked after, I know how gutting it feels when a car you've only just tken delivery of let's you down, I've been there with a Vauxhall, The GTi is a truely great car, and it would be a great shame to let it go back, without a fair trial.