Interesting topic, I am slowly working on making a dildo out of platinum silicone because the market doesn't seem to have what I am looking for.
My wife loves getting stretched by large dildos (3"+ Dia), but she can only take about 8" max length. She also loves going balls deep and when our body's are smashing/grinding against each other. Most dildos that thick are also much longer than she can take.
Since she loves feeling a horse flare, I want a horse dildo (full flare) that has a minimum Dia of about 2.75", ring about 3.5", flare about 4", with the insertable length at 8". This would be a strap-on style dildo so I can really fuck her good (we have a sex machine, but she loves my arching thrusts). There would be a "plug" that would go into the hollow section to allow for attachment to the vacu-loc on the sex machine.