The short answer is -
Not at all.
There's a few things to consider, so lets discuss those.
In case you don't have Bathmate and want to know what the comfort ring is -
The newer models of the Bathmate Hydropump, specifically - the x30, x40 and Bathmate Xtreme comes with a 'comfort ring' accessory.
It looks like this on the x30 and x40 models -
and It looks like this on the Bathmate Xtreme models -
In theory, the comfort ring/pad makes the Bathmate more comfortable on your pubic region when you pump it and leave it on.
While most guys will probably find it more comfortable than using the Bathmate without the pad, many people feel that it hinders the suction they can get.
I know I feel that that.
I never use the comfort ring.
I have never found the Bathmate (any of the models, I own them all) to be uncomfortable.
I always try to get as much suction and pressure as I possibly can, so any sort of discomfort I would be willing to tolerate.
Many guys agree with me here and we encourage you to use the Bathmate without this comfort pad if you can.
If you have problems with the Bathmate digging into your skin and pubic region, have a look at this post, this is something that you can fix.
No, you don't have to use the Bathmate comfort pad.
In fact, your suction (and therefore results) will probably be better without it.
Take off the comfort ring for your next Bathmate session and tell me if the suction isn't noticeably better.
For more information on all the models of the Bathmate Hydropump, check out Good Looking Loser's Review and FAQ.
Leave any questions you have in the blog comments section. I'll be happy to answer them.