From a financial point of view, go for it. If you can fork out the cash now, then buy it. It will much easier to downgrade to a lower cost bike later than to try to buy a higher price bike later. If you do end up enjoying your commute, your reasoning to buy a cheaper commute so that you can "preserve" your higher end bike will be more sensible reasoning for your SO. Just tell her later on that you need a cheapy commuter for commuting and to give her a chance to keep pace with you on her "cruiser". (please don't quote this to her )