If the Big 3 aren't stopping your hairloss, then please please please don't do a hair transplant. If you can't stabalize your loss, then you'll end up losing all your hair...and you'll be left with nothing but your transplanted ones. At that point...well...what's the point? The only way I'd get a hair transplant is if I'd been able to stabilize my hairloss for 5+ years.
Just my $0.02