Harman Kardon might be on the only brand that has a worse reliability rating than Onkyo, so I would go with Onkyo. Looking at the Harman ebay store, the plurality of their negative feedback is actually defective HK 3490s being sold.
My only experience is with the HK 990, both of the ones I bought from Amazon immediately went into protection mode as soon as I turned them on, so...that was the end of that.