i know that this is not an exact science but again i will put this out to other folks who probably know more than me!! i have the cb-6000s. i have been extremely comfortable using the #2 ring and the smallest spacer. i recently had the tube break and had to go without for a few days. as with many of us who engage in this lifestyle i am always trying to push my limits a little each time i can. my Wife happens to be out of town and i have the opportunity to experiment before She gets back if i want to with different combinations/ring sizes for long time wear. i am presently wearing the #3 ring with the smallest spacer and it is definately "snugger" down there yet not uncomfortable. in trying to make things stricter on myself do i gain any advantage or disadvantage by going to a smaller size ring? there is the risk that this might be too tight when aroused and i when doing my walk today i had for the first time in months a little irritation around my balls. i cant get out of the #2 but i for sure cant get out of the #3. while "looking" at things and being somewhat aroused this smaller ring seems to not allow as much movement period! and i am wondering if that will aid in my frustration of not being able to get "off" as it were. with the #2 ring there is definately some latitude of movement that allows a lot of pressure and movement for stimulation. will i also stretch and accomodate the smaller ring over time as i did i guess with the #2 from the #1 to begin with? just wondering and wanting to know some other peoples thoughts on the subject---do i need to go to the #3 or is it just a kneejerk to want to self abuse myself a little? on another similiar note?....how many people out there who wear the cb series devices can actually wear the #4 #5 size rings? im not sure i can even mash my self small enough to get in the #4 and believe me i am not large or big anywhere in regards to these devices. i am small to average at best. im not talking penis length ......im talking the circumference around necessary to even be small enough to get in the smallest size? im just wondering and not implying that no one does just ouch...how many can!!!???