It is amazing how emotional the topic of 'walking' is in our beautiful game, no matter who you talk to or where you are talking about it, everyone has differing thoughts and passions about it etc....
For me, it is all about the level you are playing at and therefore the corresponding level of umpire.
If you are playing with a full panel umpire who is getting paid to be there etc.... then you have every right to stand your ground. The umpires are there to do a job, they are choosing to be there and getting paid to be there.
However, if you are playing a level of club cricket where there is an umpire/player who is just doing it for fun/volunteering etc..... then you should always walk.
From the above 2 scenerio's you accept what you get, the good with the bad decision's from both paid umpire's and volunteer's...... we have all seen many a bad decision from a panel umpire and also getting an lbw off a player umpiring can be near impossible some days - so you accept and good with the bad no matter what.