within 6K range or above,
You only have Lenovo or Acer.

Aftermarket laptop model
On hardware side, you may refer to equivalent Sager model.
However the QC and warranty side, each aftermarket vendor set difference standard, so you might want to do some research first.

Based on my personal experience.

I would go Lenovo because:
1. Legion is flagship model; while TUF is not.
2. Lenovo have better aftersale service compared to Asus.