I bought a N97 replica from chinese mobile series, It has a Mobile OS MTK and version MT6227. What are the support and features it has, is it better than Symbian??

MTK is popular among chinese set only and it do not support third party software installation.

Symbian is much better

Ya its true, most of the chinese phones are based on MTK.

All Range of MTK chipset like MT6225/MT6226/MT6228 , produced by MediaTek (http://www.mediatek.com), They are integrated chipsets, processors based on ARM7 EJ-S, slow to the current standards (below 100 MHz clock), but in contrast, are much cheaper, hence the popularity among the Chinese manufacturers.
The external appearance and the visual interface, varies widely according to the apparatus, but the basic characteristics of devices based on MTK chip are:

• Support for audio files in MP3 , AAC or WAV; 
• Supports 3 gp videos (with the H.263 codec) with a resolution of 176 x144 and up to 12 FPS; 
• Reader e-books ", which only supports TXT files; 
• Calendar, calculator and some simple applications; 
• Less than 1 MB of internal memory free; 
• Support for cards up to 2 GB (and some of the 4 GB cards that do not use standard SDHC); 
• 220 x176 or 320 x240 screen, with touchscreen; 
• Not support the installation of applications; 
• Includes some simple games in Java (which runs using the native support offered by the processor, more below), but does not include a JVM, which prevents the installation of other games or applications in Java; 
• Camera of 640 x480 ( the images are interpolated, resulting in 1.3 MP, 2.0 MP, 3.0 MP, or whatever the value included in the specifications).