Wirenuts

[Jimmy7]

I have switched to using 3M wirenuts, because the red/yellow and orange/blue seem to cover any combination I run across. I was using and still have some Ideal B2 wirenuts. I actually looked at the listed combinations of the B2’s and noticed that they can handle 2 to 6 #14 solid, but it doesn’t list multiple 14 solids with say #18 stranded for a fixture wire or smoke detector or something like that. I’m sure I’m not the first or the last to use these in this type of combination. I pre-twist and make my connections tight, so no concern there. I was wondering is this just a testing issue, is the testing expensive?