I have imported multiple high value items from US and Germany. I have an IEC registration as an individual proprietorship company.
You must pay through wire transfer or any other formal methods and engage a customs clearance clearance agent who will file the papers and do the clearance on your behalf. They tend to charge duty on the basis of HS code on the total landed price.
Make sure you do not import any used items, as they tend to go into a different loop and require a certification from a chartered engineer from the source country or the destination country on the refurbishment and value of the goods. If customs see any junk items being imported, they have the right to seize and destroy the item. So it is not advisable to import used audio equipment in bad condition.
One more thing, customs don't care if you are importing for personal or trade use as long as you have an IEC code. In fact importing for personal use, can get us into trouble. The HS Code can be redesignated and charged a higher customs. I recently had that scare, where the item was being redesignated with a different HS Code called "others", which would attract much higher duty.
As regards imports through couriers such a DHL or Aramex is concerned, it is fairly smooth but good for smaller value items under 1.0 lac. Duty can be anything on the basis of customs valuation. Usually they are reasonable for items they understand.
Hope this helps.