Sony Xperia P LT22i HDC N7100+ (S7100) UMI X1
The closest phone in terms of performance is the Sony Xperia P so we will use this phone scores for comparison with out MTK6577 phones.
If you look at the first 3 items on the list: RAM, CPU integer and CPU floating point, you see that all are similar in performance. The Sony Xperia P uses a NovaThor U8500 1ghz dual core processor and the numbers vary just a little, so we can say that the MTK6577 and the Novathor U8500 are equal in performance (although the pics show the MTK6577 having marginal lead).
The RAM speed on the 2 Chinese phones are actually faster. This may be due to the DDR3 RAM being used.
When it comes to 2D and 3D graphics, the Xperia P pulls ahead due to it's superior Mali 400 GPU. The difference in speed is roughly 25% faster than the dated SGX531. It shows the Xperia P having a Mali 400 MP GPU but my research indicates that the Mali 400mp is actually a single core GPU running at 340 mhz used here.
The UMI X1 lags behind because it is the only phone with HD 720 resolution so the GPU has more pixels to push but the scores of the UMI X1 are respectable.
This is the real way to read the Antutu benchmark and not just look at the full score.
The MTK6577 is indeed positioned as mid range with performance close to that of the mid range Sony Xperia P. I have used the Xperia P and did not find and performance difference in normal usage. In fact the MTK6577 phones appear smoother due to Jelly Bean.
We now await the arrival of the quad core MTK6589 phones arriving soon. Production should be in full swing in March with many phones releasing in quantity in April.