So I just got my first two urethral sounds and damn are they different. One is silicone and about 4 inches long. It has raised swells that are rather thick going down the insert able part. http://www.amazon.com/gp/aw/d/B00BPPEDP2
The other one is a cum thru style that I didn't like very much. For one I had to remove my Prince Albert to get it to fit. Second it's way too short and I had to hold it in with one hand while I used my other for playing. Felt very strange orgasming through it, just wish it was a hair thinner and was longer. I could stand both to be longer actually. Here's the second one http://www.amazon.com/gp/aw/d/B00BPN40I4/ref=pd_aw_sbs_6?pi=SL500_SS115
For it being my first time inserting I was very surprised at how good it felt. Sure it stung a bit at first but I expected that from when I got pierced. The deeper it went though the better it was. Definitely going to keep experimenting.