FX Intelligence the service I highlighted over a year ago and which allows you to monitor broker performance by tracking down their rates for various currency pairs over a time span of a few hours and up to one day has made a significant step forward by striking a deal with MB Trading - it now appears live on MB Trading's site showing MB Trading's performance vs other brokers. Go to https://www.mbtrading.com/pricing.aspx and click Spreads. MB Trading is compared against 4 other US brokers with them having worser spread than MB on average (on FXIntel's site there are about dozen more, some with better spreads). First of all congrats Brian for keeping up the good work.
What's more interesting though is that the US industry is slowly becoming more transparent (and not thanks to NFA's efforts) - more and more brokers now show such metrics as their average spreads on their respective homepages. We have Oanda comparing itself to four other US brokers (almost always Oanda's spread is better but on FXIntel's site it's far from that). We also have Interbank FX showing it's lowest and average spread as well as execution percentage and execution time. This is great start for more transparency in this industry and I hope to see more brokers follow suit.