Being HIV+ myself I do practice sero-preference in dating. I usually find life is a lot easier dating another poz guy. I enjoy being around someone who knows how to support me because we have a shared experience with the virus. I have tried dating negative guys and it usually doesn't work out for some of the following reasons:
a)He tends to treat my cock like it's kryptonite and won't even let his hand brush against it even through my jeans and underwear.
b)He is a bug chaser (sick, sick little fucks they are)
c)He freaks out and thinks I'm dying every time I cough or sneeze.
d)He constantly uses terms that are offensive to many poz people. (I'd give you list but it would spark another thread war)
Also there was an event that set me leaning more towards the poz guys these past few years than any of these other things combined. The first time I had sex with my last BF I was going down on him and I got a bloody nose, I mean a real gusher. Before I knew it his junk was covered in my blood. I cannot accurately describe the terror and panic I felt in that instant. I was simultaneously terrified for his sake and terrified he would freak out and run screaming into the night never to speak to me again. Fortunately for me, he reminded me that he was poz too, a fact that had escaped me in the heat of passion. The point is that in that instant my knee-jerk reaction was to haul him into the bathroom for a
Silkwood style scrub down. The idea that he just as easily could have been sero-discordant to me pushed me towards avoiding that situation in the future if possible.
Anyhoo, this thread is kinda a downer and thems my 2 cents on the issue.