I can see taht Eddy, wouldn't ever have thought about doing it though. People can be rude at times, unfortunately more people are rude then nice in the game because they can hide behind there avatar.
I managed to get around those awful feelings of loss and guilt when, after some months at 80, I finally had to abandon Felin, my first level 10 cat from Teldrassil. (There's a reason for the similarity of our names, by the way – but that's for another time. Suffice to say that the "-in" ending of my own name is a feminine diminutive.)
I knew it would be hard, so I planned it in advance. I had Loque (my first SB) in my stable alongside my original cat and with the same name. Somehow the spirit of one transferred to the other. So even though the time eventually came to make way for the other SBs and a devilsaur (now replaced with TB) I have not really abandoned my Felin at all.
Yes, yes… I know I need help!
Oh I nearly forgot… the answers to the original questions are: 1) yes; 2) no; 3) it depends what you mean by 'useful'.
seeing as my guild lets me raid as bm and use what ever pet i want without any bitching, its really up to you, go with a class and pet that everyone else is using (mm and wolf) or sacrifice that few hundred dps, and raid as a spec you love(what ever it be), using a fucking bad ass spirit beast, and in the end still down what ever boss and get your mad loots