I have switched sides so that I have the left channel in the rigth ear and visa versa, I have done that because it made it possible to use the bend on the q-JAYS to get it further in the tip and closer to my eardrum..
they can be pulled out easyli, so no problem there..
It is just a custuom earprotection with a special hole for the q-JAYS and a bigger hole leading to the ear than a normal piece, so if you are going to you lokal shop they will need to borrow your phones for a weeks or so..
It is BTW made of silicone
I showed them a picture of a pair of er4 with customtips and told them I wanted something similar, they got it right in the 2. try...
I also asked for a model that fills up the outer ear instead of just a tip too be inserted, so that they would isolate better (I use them at work, to protect my ears from noise).
The biggest difference is the bass, It is deep, powerfull and crisp, I get about the same amount of bass as the shure e-500, but much more sharp/crisp than my shures...
They are also much easier to insert and take out than universal tips, the only downside is that it takes ½ a minute or so for the tip to warm up and expand before I get the full effect of the isolation and bass, it also gets better over time, fitwise that is..