If you're totally confused by now as to which is the "best" product out of this round-up, I can't say that I blame you. As I was writing all of this up, I constantly thought I had found the "winner". But when I moved on to summarizing the next set of data, I would find my favorite not maintaining its top place.
But before I get into the final ranking, let me finally answer the question: Do less-expensive two-antenna draft 802.11n routers perform as well as more expensive three-antenna products? Looking back over all the data an analysis, I have to say, no, they don't. But the difference in performance when both products types are run in the default 20 MHz bandwidth mode may be undetectable in real-world use.
Put more simply: Yes, there can be a difference in wireless performance between two and three antenna products, but not enough that it's worth paying a large price premium for.
With that out of the way, let's start ranking. Although it did appear in some of our "best" summary charts, the D-Link DIR-615's performance over range and its weak showing in our routing tests force me to put it at the bottom of the pack.
The next product that I have trouble recommending is the Trendnet TEW-632BRP. Although it has decent wireless performance, including staying connected with a lower signal than any other router in this group, its tendency to lose routing speed over time and the fact that it doesn't properly default to 20 MHz bandwidth mode mean that I can't recommend it.
Of the remaining products, I think that the Belkin F5D8233-4 is the strongest overall wireless performer. But that conclusion is based on limited open-air testing. I would be more comfortable recommending it if I had been able to test it with the Azimuth system so that I could directly compare it to others in the group.
This leaves the D-Link DIR-625 and Linksys WRT150N and 160N. All three have similar performance running downlink, but the Linksyses clearly outperform the 625 on uplink. The D-Link also disconnects slightly sooner than the Linksyses. But since the WRT150N is being discontinued and it also doesn't properly default to 20 MHz mode, I can't recommend it.
So between the D-Link DIR-625 and Linksys WRT160N, I choose the D-Link DIR-625. Its has the fastest router of the bunch, handles the most simultaneous connections and includes StreamEngine automatic QoS. And while it isn't the best wireless performer in my tests, the 625's wireless performance is good enough to provide better wireless performance when paired with a matching draft 11n client.