I know people that have tried them both. The Alphatek is OK but difficult/complicated to use compared to the Megger MFT or Fluke. The Kewtech is too easy to blow up where the Megger MFT's are easiest to use, indestructable even if you put them accross phases on the wrong range and push the button, and come with a 3 year warranty.
I have had the new MFT1553 for 6 months an its great.
I got emailed a promo video for it you can see at
YouTube - Megger MFT1553 Multifunction Tester