Questions about a part of a Eurofighter Typhoon I got (drag chute release switch)

I got this bit which was removed from a RAF Typhoon (ZK347) it is the switch used to deploy the drage chute.
I am hoping someone here might be able to answer some questions regarding this item, well the first questions are more of a general one relating to the drag chute, first are the drogue chutes re-useable? why does the Typhoon need one, i suppose that could be applied to other aircraft, seem that some have them and some don’t, i know the Tornado never had one, that had other ways of slowing down after landing, my only guess is that other methods involving more complex mechanical parts are more likely to go wrong and to costly and time consuming to repair?
I have seen videos of Typhoons landing and not using the chute, and some where it does, I thought it might be down to the runway conditions, like if it’s wet, but it looks like the runway is dry when the chutes have been used, so what are thee factors that a pilot would choose to use the chute, are there any certain criteria that says it should be used if landing above a certain speed or certain runway conditions, or is it just down to the pilots discretion?
Finally, this is the only question that pertains to the switch itself, it seems to have 2 ways of being operated, its on some spring and has 2 projections each side, using 2 fingers you can pull both together, but you can also use one finger and pull just one which instead off pulling straight out it moves at an angle. bit hard to explain in words so hopefully it makes sense!  would this how the chute is released after it has slowed the aircraft down? so 2 finger pull to deploy it then single finger to release, or maybe the other way round?