TRS4

Hopefully someone here is an expert on wheels and offsets and can provide me some "real world experience and advice" I am interested in acquiring a set of Rota RKR Wheels. PCD 5x114.3 in 17 inch. Issue I have is that I currently have a set of wheels that have printed the following 17x10 with ET 15 (doesnt state whether its a + or - ET 15) which fit like a glove! But are shit wheels I am trying to figure out what my options are in relation to the Rota RKR offsets and what will work. 17x8.5 -10 or 17x9.5 -20 Hope someone can lend some advice on this