Sorry, but since I don't have a solid ferrite rod that size to compare it to, nor would I want to pay the price such a rod, I can't answer you question. I can tell you that it is much better than the stack toroid rod that I wrote about that using the FT140-61 toroids. 

I was quite surprised at how well it the stacked toroid loop worked compared to 1 meter air loop. I probably will not do any more experiments with this as a receiving loop, as my plan is to experiment with using it as a transmitting loop.  I plan on placing the toroids on a copper pipe, rather than a wood dowel rod, so I can do some cooling. I have been operating a lot of JT65, which allows you to DX with very low power. I bough 46 of the toroids so I can build several ferrite transmit loops. 

I don't know how long the supply of the toroids will last. I think that if you offered the eBay supplier $35 to $40 delivered for 10 toroids he will take the offer. They are not a standard size, but are made by Fair-Rite, whom is a high end manufacture of ferrite. You would normally pay $10 a pice, or more for a toroid like that. The inductance for ten turns of wire on a FT240-61, which is the largest core that Fair-Rite makes in that mix, is 20uH and it weights about 106 gm, the toroids that the eBay seller is offering have a inductance of 36uH and weigh 136 gm.  

Everett N4CY (new call)