Tubs

Ok few noob questions

1. Should I put sealant in perfectly healthy tyre? I have tufo extreme.

2. Should I carry spare stretched glued tub AND sealant on a ride or just the spare if I have sealant inside tyres?

3. In case of puncture when I take the tyre off the rim how much should I bother with getting the glue off rim? If I dont would the pre-glued spare tub stick to it well?

4. I have 60mm rims and vittoria corsa cx (III I think) tubs and the shop said the valve core comes off with the tool (which I have) whats the difference between that and extensions? Is one better than other?

1. No.
   
2. No, but see answer to 1.
   
3. None at all - the glue is there to bond to the glue on your spare tub. The pressure in the tub will form a partial bond between tub tape and glue, and loose glue and glue that wasn't displaced when you removed the tub.
   
4. There are fixed and free valve extenders.
   
   

For the fixed extenders you remove the valve core, add the extender, then put the valve core in the extender. If you use these you must have them in place before you mount your tub. It can't be done after the fact. They leak, too, unless you use plumbers tape on them. I think they are shite.

The free extenders, like the Topeak ones which I recommend, simply screw down on to the exiting valve stem. A nifty little insert inside them interfaces with the core allowing the extender to open and close the core. You screw down the extender, use the extender to unscrew the core, pop the pump on, do your business, pop the pump off, use the extender to close the core then remove the extender. You only need one, and you carry it with you on your ride.