I ordered a battery on 5/19 for a time-sensitive phone repair. Quoted the cust a repair date 5/27, part delivery via USPS quoted to me on 5/25. Sweet, plenty of time. Yeah... I died a little inside when I saw the words "shipping partner" on the tracking. As I write this, it is late evening on 5/24 and tracking has shown "Arrived Shipping Partner Facility, USPS Awaiting Item" since 5/20. Even if it somehow gets to USPS tomorrow, it's still 3 states away and will take a few more days to get here. I had to reorder the battery elsewhere with overnight shipping to meet SLA, so thanks for costing me money.
I will never understand why any retailer uses these middlemen instead of shipping directly with USPS or any other legitimate shipper. I have never ONCE received a package handled by OSM or any other shipping partner in under two weeks. They sit on packages for weeks, bounce them around to different states, or you'll see multiple "arrived at facility" scans at the same location before they eventually, HOPEFULLY, hand them off to USPS. Every retailer should be required to disclose use of shipping partners so customers can order elsewhere, or at least not be surprised when they have to wait weeks for domestic shipping. Do yourself a favor and don't shop with any retailer that uses shipping partners, and cancel your order if you see one on the tracking after purchase.
I'm not even going to bother arguing with the seller or contacting OSM for some canned excuse, just filing a chargeback. Ridiculous.