Hi Guys,
This is a great question. I will try to answer this the best I can. This is what it says for the Koa Bongos at the Volcano web site
Volcano Percussion - Hawaiian Koa Bongos
These beautiful drums are made from the same trees as our Jack Costanzo Signature model of bongos. This wood is the high grade Koa used throughout the world for fine furniture, guitars, yacht interiors and architectural designing. Hawaiian Koa only grows here in Hawaii and is a renewable resource. It is a wonderful tone wood and makes a superior and original one of a kind set of professional bongos.
Our Hawaiian Koa Bongos can be ordered in
Premium or Partial Curly Koa. -----------------------------------------------
Volcano Koa Bongos Feature:
Master-crafted Stainless Steel Hardware
buffed to a Mirror Finish
Insides Finished
Texas Kip heads
Stainless Steel Skin Hoops
5/16” Stainless Steel lugs
Stainless Steel Washers
Rubber Gaskets on Center Block
Stainless Steel Backing Plates
Staves dowelled together
Dupont Polymer Finish
Stainless Steel Embossed Nameplates
Size: 7” & 8.5” x 6” or
Size: 7” & 9” x 6”
5 Year Limited Guarantee
Made in Hawaii, USA
Optional Remo Heads
This is what it says about the Jack Costanzo Model.-------------------------
The Jack Costanzo Signature Bongos Feature:
Hawaiian Full Curly Koa Wood
Master-crafted Stainless Steel Hardware buffed to a Mirror Finish
Insides Finished
Texas Kip heads
Stainless Steel Skin Hoops
5/16” Stainless Steel lugs
Stainless Steel Washers
Rubber Gaskets on Center Block
Stainless Steel Backing Plates
Staves dowelled together
Dupont Polymer Finish
Stainless Steel Embossed Nameplates
Jack Costanzo Signature Name Plate
Size: 7” & 8.5” x 6” or
Size: 7” & 9” x 6”
5 Year Limited Guarantee
Made in Hawaii, USA
Optional Remo Heads
Premium or Partial Curly grade wood on the Koa line of Bongos -- or -- Full Curly Koa grade on the "Mr. Bongo" Jack Costanzo Limited Edition Model line of Bongos.
VinnieL- to answer the question directly the difference is the grade of the Wood, Full Curl rare Hawaiian Koa wood , The Jack Costanzo Stainless Steel Embossed Signature Name Plate , The Jack Costanzo Limited Edition Model.

- Koa Wood Grades
I hope this answers the question. The Full Curl Koa wood is the rarest and most beautiful and is used on Volcano Percussion's top of the line Congas and the "Mr. Bongo" Jack Costanzo Limited Edition Bongos . ABAKUA thanks for the complement.
Thanks
Mike