I am really liking BuyandShip. At 6$ per lb, its damn cheap and they allow consolidation as well (although I never tried it)
Since Buyandship doesn't technically support usage of IEC, its upto the
carrier on how an item is cleared cause you might still need to submit the KYC docs to the carrier. In my case, my KYC docs are already with Aramex (IEC and all required documents), so it automatically gets cleared with IEC.
And the other thing is that you can declare the invoice value as you'd like

and I have never got any query for additional documentation as part of clearance process. With Aramex ShopAndShip, they don't submit the invoices properly so customs end up asking for more docs delaying clearance.
With respect to time, once the package arrives in their China warehouse (provided you have pre-declared it), the item automatically gets forwarded to their HK warehouse. Once in HK ware house, you can consolidate with other shipments as needed.
China to HK - 3rd day (excluding weekends so if there is a weekend in between, it would take 5 days)
HK to India - Usually gets shipped the next day after payment. In case of my recent shipment, I made the payment on 8th, shipped on 9th, customs cleared today ie 12th. Once cleared, it gets handed over to Delhivery, so another 3 days for me to receive it.
The only issue is, for small items, the customs clearance charge is a lot Rs 354, so would need to bundle items together to save.