I've used 4D and Pacific.
Pacific has better communication, but they don't seem to inspect the tools very well upon return or before shipping. I've been shipped two different crown cutter 'sets' that had broken, dull, chipped, or missing pieces. Luckily, those issues never impacted my own use of the tools, however. So, my only involvement was notifying Pacific that that tool had X issue(s), upon receipt.
4D is good, and I've never had a problem. I'm sure that it happens, but I've never had a problem. Always good condition reamers and tools.
But it bugs me slightly that there's no human element in standard transactions. It's like dealing with a vending machine:
Put your money in the robot. Tool shows up in mail. Robot sends an email reminder that your time is limited. Return tool to distant robot by dropping it in a mailbox. Robot says thank you a couple days later.
(I live one shipping day from 4D. So, the tools ship both ways quickly. I have to need the tool before I order it. Otherwise the tool has to be returned before I get to the job.
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