Should i order a Z15 from Bitmain

Hi everyone
I was hoping to get some feedback and opinions on ordering a Z15 or two from Bitmain directly. If anyone thinks the Z15 is a bad choice (and why) and if they think that there are better suppliers out there that could get me the rig (or a better rig) sooner.
Quick back story. I have 3 computers at home that are mining currently. I have very much been bitten by the mining bug. I have an area in my home that i can make into a mining room, however, the quieter the machine the better. I have been trying to purchase some used equipment from Alibaba for some time and frankly the pricing has been insane. For example i was just quoted $9000 for a Z15 from a reputable vendor. I mean, you can order one from Bitmain for October delivery for $4000,am i missing something? Any thoughts would be greatly appreciated. I should perhaps mention I’m not interested in any sort of mini miner, theoretical earnings need to be somewhat significant or it just isnt worth it for me.

Thanks for any input
Nit

If you’re in the USA there’s a 25% tariff I believe, so 4K is going to go up. Give some thought to big vendors like Coin Mining Central, etc. btw, z15s are Not “quiet” miners.