If you've been saving for your house really well, then just go for the extra $150. So you're going to be paying $150k plus on a house probably...whats another $150 on bike. Plus, if your $400 used bike starts giving you problems when you are up to your eyeballs in a mortgage and home related expenses, you're going to hang that bike up real quick. It IS worth it to make a good investment on a fixie the first time around if you can swing it becuase you will enjoy it.

I saved my money to buy a house so hard and long,I said f-it time to treat myself, and I picked up an IRO Mark V. That was a few months ago, I'm in contract now to close on a property, and quite honestly, I can barely feel the dent that the bike put in my budget.

Take care, and good luck with the house/bike,

Kevin