not trying to put a damper on anyones day here but these are going to cost 1500 a piece- 6k for wheels isnt exactly cheap.
Here is a basic overview. When looking at wheels you need to look at cost, size, intended use, as well as styling.
Forged wheels regardless of 3 piece or not are usually going to go for over $800 a piece brand new. Forged wheels are much stronger, usually lighter, and in most cases are a finer product since they take more time to make, whereas a cast wheel is a much cheaper option with wheels ranging from 250-500 a wheel.
Rotiform Cast BLQ- $300 a piece
Rotiform Forged BLQ- $1250 a piece
the reason is the fact that Rotiform gets all of their cast wheels manufactured in China and then shipped over at an extremely cheap rate. Whereas each forged or 3 piece wheel is hand built using a much more expensive process. However these wheels are much stronger, lighter, and have a higher quality of finish to them.
Determine what style of wheel you like, and what cost you can cope with.
Personally I love HRE Wheels- but cant shell out $6k for wheels when I would rather begin the process of single turbo'ing my car.