I've mainly used Amazon, Newegg, eBay, Walmart and KEH with both MyUS and Stackry. I prefer Amazon because I mainly buy used items and Amazon sellers that sell used items usually undervalue what they have since they're trying to win at a numbers game with other competing sellers on Amazon. For payment, I used to have virtual credit cards through a service/company in Europe, but I forget what it was called. These virtual cards automatically approve any billing address which allowed me to use the same address for shipping and billing on sites that only accepted cards with a billing address inside the US.
With MyUS, I preferred DHL because there was no KYC back then and DHL handled the entire clearing process without question or confirmation but the DHL office here didn't do final delivery — I had to go to their office and pay duties and then pick up my parcel. So customs was usually around a third to half of the value of the shipment including their own fees. They didn't include the cost of shipping in the calculation.
FedEx wouldn't clear customs on my behalf and wanted me to go to Delhi for a shipment that was over 100k (for which I was told that I needed an import permit). Customs officials didn't accept ignorance of the regulations as an excuse and I was not allowed to claim that shipment, it was confiscated by the Government of India. Sixteen years later, I'm still a little bitter about losing that one. I had a similar experience with UPS with an error made by Bitspower's Hong Kong office. So I've not used FedEx or UPS since then.
All of that was with the previous government so 10+ years ago.
With Stackry, I use whatever option that does final delivery through the post office. There is limited tracking and no insurance this way, but it's affordable. I paid around 3k customs for two motherboards that costed 6k with 4k extra for shipping — this was before the lockdown. I opted to pay at my local post office since I wanted to inspect the parcel before accepting it. The postman did offer to deliver it with payment being made directly to him.
Sometime after that shipment, I bought a used Socket 370 motherboard for $25 and there was no customs on that shipment. Randomly, none of my shipments from sellers in this part of the world (Singapore, Malaysia) have attracted customs when delivered by the post office.
Ha, I did not know that. Looks like Stackry does have Aramex as an option though.