When ya get a screw or nail in your tire with a tubles rim set up, its generally a very slow leak, more than enough time to get to somewhere to fix it, and I agree the slime type stuff is more a mess than anything else. If it not a very slow leak, slime wouldnt work anyway, it would just blow out the hole.
best thing is to buy youself a small compressor and carry on the bike and if you have to fix a tire on the road.
Get a stopNgo tire plugger kit, this is not just a hand inserted plug, it actually requires a compression tool to insert the plug.
they are about 31 dollars and I luv it alot.
although the repair is named temporary, I've ran these repairs well over 100 mph, this kit will get ya full life out of you tire, no MC shop is going to repair a tire nowadays.
Nothing like buying a 200 dollar tire and have a screw in it 500 miles later, and then having to buy another tire.
they offer 2 types ,a manual compression toll or a gun type, the gun type sometimes doesnt insert as well as the manual tool and ya have to run the plug through the gun a time or 2 to stretch it. I can vaulch for the manual compression tool type, works great.
also carry stick ropes incase ya get a cut and not a hole