I have some experience with these Chinese knives. Yes they are well made but the steel used is not as good as top end knives like Cold Steel.
If you want good edge retention then you need steel with high carbon content. If you want good rust resistance then you need high chromium content. Many Chinese knife makers will label their steel as 440 steel. While this may be true, there are different types of 440 steel:
1)440A (a.k.a. X65CrMo14, 1.4109, SUS440A, Z70CD14, 7Cr17, 65X13, S44002, XT-70, AUS60, 12C27, 12C27M): C= 0.65 - 0.75, Cr= 16 - 18;
2)440B (a.k.a. X90CrMoV18, X91CrMoV18, 1.4112, SUS440B, X90CrMoV18, X90CrMoV18, 8Cr17, 17042, X90CrMoV18, S44003, 2RO189, N685 EXTRA, R17X, R17X, RF90, RS11, Coracid4112, RM189, LO-R 4112, OCR6, RFSh2, Korronit-C, PMCo189, REMANIT4112, X90CrMoC18, NIROSTA4112, K90L, ARGESTE 1.4112): C= 0.75 - 0.95, Cr= 16 - 18;
3)440C (a.k.a. X105CrMo17, X90CrMoV18, 1.4125, SUS440C, Z100CD17, Z100CD13, X102CrMo17KU, 11Cr17, 9Cr18, 9Cr18Mo, 9Cr18MoV, 17042, S44004, N695, T10MO, CTS-40CP, XT-80, LO-R 4125, RFSh6, 95X18): C= 0.95 - 1.20, Cr= 16 - 18;
All of the 440 series have the same Cr content but 440C has the highest Carbon content hence the best. They, like all stainless steel, are however very hard to heat-treat so you’ll have to rely on their carbon content for edge retention.
Many knives & swords in my country are made from spring steel - the leaf springs taken from junk vehicles. This steel is a.k.a. 5160 steel. While this type of steel has a bad resistance to rust (Cr= 0.7 - 0.9) and lower carbon content (C= 0.56 - 0.64) than the 440 series, it can be heat treated and when done properly, it has a very good edge retention.
I hope this helps. 