I use the dubro valve in two planes, I did get the rebuild kits to, but haven't used them yet..no problems thus far and they have been sitting around for 6 to 9 months between using them..but many swear by the dots..I am keen to try these out myself..but as for a refueling valve..haven't had a problem with the dubro unit...when you think about it you can see that these valves have the capacity to cause problems but you do need something in fully cowled engines