Ashhar Farhan, if you do not know I do not know who would.
From what I have been able to find on the net, there were a number of "clones" of the HF Signals version of the uBITX. Most were copies of the original BITX20 single band radios. I would not purchase one that is not from HF Signals, as the information is hard to find. This means that you want a v3 or later microBITX.
The differences between the versions are best recorded on ubitx.net. Without going into detail, most of the differences were to fix audio issues and key clicks (v3->v4) and then spurs and harmonics issues (v4->v5) and finally to include a touch screen interface (not sure I would call it graphics, as the display is text-based)(v5-v6). The v6 is also the first version that you can order a "full" kit that includes the enclosure from HF Signals. There are still some enclosures for the v3-5 that you can buy, though I believe that these will get harder to find as they are no longer in production.
If you do purchase any version prior to 5, you should do a harmonics and spurs test to verify compliance with the FCC (by your call I looked up that you are in the USA). Ubitx.net has the fixes listed there as well.
Hope this helps you with your purchase choices. They are MY preferences/thoughts, you will need to verify for yourself.