What is Reddit's opinion of COOFANDY Men's Business Suit Vest,Slim Fit Skinny Wedding Waistcoat, Dark Gray, Small?

From 3.5 billion Reddit comments

I want to treat myself and get formal outfit, something that says formal but modern + relaxed/slightly casual. I think I really like the look of a slimline vest without the suitjacket (similar to this look). If it matters, I am 6ft with a slim build.

If I am feeling like splurging on myself, would it be worth it to get the full outfit custom made, or would I be better off only getting the shirt custom and maybe just get the other pieces from elsewhere and get them altered as needed? Even if in theory I don't think a suitjacket looks my style, should I still get one if I am getting the rest of the suit, just to complete it? Is there anything I should consider that as a fashion newbie I might be missing? If I don't necessarily think I need the suitjacket, is bespoke still something worthwhile?

Edit: There seems to be very strong sentiments about vests without a jacket. So strong that I find myself having to figure out if this is legitimately an allround bad look, or if this is simply some weird fashion gatekeeping in traditionalist circles.