I became a sedevacantist about 4 months ago and I have no regrets. To me, it is the position that makes the msot sense.
However, the hardest thing about becoming a sedevacantist is acknowledging the fact that all the novus ordo priests ordained in the new rite of ordination are not really catholic priests. So what are they? "Vatican II priests?" This is something I really struggle with because believe it or not I have met some very fine novus ordo priests who from my opinion, genuinely mean well but have this weird type of neocath allegieance to the pope. A lot of these priests are very conservative, very traditional, even say the TLM mass. A few of these priests, either diocesan indult or FSSP, have been very good confessors. Ironically, some of these conservative novus ordo priests have actually been more harsh and direct with me in the confessional than some of the SSPX/CMRI priests I have confessed too. For that I will always be very appreciative.
Even though I am a sede, it just seems crazy to me that a super conservative NO priest who is just hanging on to the NO out of a false sense of obedience is not really a priest. Since he is not a priest, would I just call him MR. Smith instead of FR. Smith? Even though I accept that Pius XII/possibly Cardinal Siri was the last visible pope, this just seems kind of crazy.
Go with your instincts -- it IS crazy.
I don't think we can say that no Novus Ordo priests have valid orders.
I think it's more likely that the majority of the Novus Ordo establishment has some degree of error, most are weak, most are not malicious, etc.
I think one of the biggest problems in the Traditional Catholic world is the fact that people talk about "Sedevacantism" as if it's just a decision about whether post-Vatican II Popes actually held the Papacy at all. No, it's a LOT more than that --
Sedevacantist should be "Ecclesiavacantist" because it's always about the entire Church, not just the Pope.
"Sedevacantist" implies that a good Catholic is just judging that the man commonly known as the Pope isn't a pope at all -- or if you don't like the term "judge", he's just calling a spade a spade, using his common sense,
sensus catholicus, or what have you. But it's rather innocuous -- it seems to only affect one man -- the man popularly known as pope.
But really it's much, much more than that. The status of the whole Novus Ordo establishment is at stake -- hundreds of thousands of priests, many bishops, the entire Church hierarchy (without exception; not just a few dozen Masons), the validity of the Mass, etc.