Peak hashrates are the same, give or take. The algorithm is so well known now, there's not a lot of difference between the current mining applications.

To compare miners, you really need to look at valid shares produced per day or per week. Average hashrates and uptime are actually more important if you want to maximize your profit over weeks or months, and Pro Miner is tuned for this, not peak hashrates.

In fact, Pro Miner is the only miner I know of that reports Average Hashrates over days and weeks. It also produces very few stale shares - about 0.5% - as shown in the research I published on Local and Global Work Sizes: (reddit)

Also, we run Pro Miner on our rigs and get over 99% uptime with very little maintenance. It just keeps going!

But the main point of Pro Miner is of course the architecture. The miners run as Windows Services and the Graphical Control App can be run remotely, so you can monitor all your rigs in one place and hardly ever need to log in to your miners.