QiYi have a reputation for making great Pyraminxes, the Bell V1 and V2 are regarded as some of the most iconic magnetic pytamines on the market. The QiYI MS takes heavy design notes from the Xman Bell V1 with a simple and fast internal mechanism and a similar satisfying feel and sound to the original bell. This cube tends to feel blocky and very stable with a distinctive tactile feedback to each turn.
This puzzle does come a bit tight so I recommend backing off all of the screws by roughly a half turn, This helps wake the puzzle up without sacrificing much stability.
The main downfall of the puzzle is the tips, out of the box they are un-usably fast and can cause a lot of +2s if you are not careful, an easy fix for this is to take some extra magnets which you may have laying around for free if you own any YJ big cubes, and stick an extra magnet on top of each of the tip magnets without any glue. This takes about 2 minutes to do and immediately fixes the uncontrollable tips making this pyraminx punch well above it's weight.
If you are looking for a simple, reliable pyraminx and are willing to throw 8 extra magnets into this thing and tinker with it a bit it is an absolute monster of a puzzle for 10 dollars. VERY competitive to the YLM in performance and price and I typically find QiYi's quality control way better.
TL:DR
Good triangle, bad tips, add magnets to make good tips and great triangle.