I've taken the 50/50 option. Without it in Canada we wouldn't have seen JB able to haul in Vettel as quickly as he did in those last few laps but in other times it's not helped one bit, Schumacher in Canada also springs to mind, where he was doing a great job but was unable to hold back the cars behind him purely due to DRS.
If I could make any changes at all (and I think it's sorry to say but DRS is here for a long while now) is that I would have a limit on DRS operation rather than the 1 second gap rule. There could still be DRS dead zones for safety reasons where the use of DRS would be electronically prevented but at least by limiting the number of operations, the car ahead could use it to prevent a pass as well as the car behind using it to create an opportunity. The time to use DRS becomes part of the race strategy then rather than just when you are one second behind.
If I could make any changes at all (and I think it's sorry to say but DRS is here for a long while now) is that I would have a limit on DRS operation rather than the 1 second gap rule. There could still be DRS dead zones for safety reasons where the use of DRS would be electronically prevented but at least by limiting the number of operations, the car ahead could use it to prevent a pass as well as the car behind using it to create an opportunity. The time to use DRS becomes part of the race strategy then rather than just when you are one second behind.