At 1:42am ET?
Which would be better for me to be: A Catholic who had grave personal doubts about the Immaculate Conception or a Protestant who believed strongly in the divinity of Christ?
There's not a straight-line comparison to be made there. Would it be better to be a Catholic with "grave personal doubts about the Immaculate Conception" but no doubts about the divinity of Christ? Yes. But there is a certain hierarchy of truths here. One does not become "less-true" for being less important, but either person who doubts the divinity of Christ is in big trouble.
your (Catholics in general) belief rests upon the idea that there is a monolithic true Church that is infallible.
Not exactly. It rests on an eternal God who continues to communicate with His people in the same way He always did. Your belief system must rest on God ceasing to communicate with us. Or, in other words, an unchanging God changing.
But if the people in the pew ain't having it, it doesn't really matter that the Church is infallible does it (at least to said people)?
Does that analogy fit throughout Scripture? When God spoke infallibly through a prophet did everyone immediately change their beliefs and behaviors toward God? Or were there those who continued to act and say "his system rests upon the absolute authority of Moses (and he would point out guided by God, but how can we believe this?)." Isn't Scripture just full of hundreds of examples of God laying down the law infallibly through His church and the people ignoring it?
Us Pentecostals are hardly cessationists. God continues to communicate with us through His word, His Holy Spirit and His church. We just disagree with you about the definition of that last noun "church."
While I'll grant that I did not state it very well, I think it is safe to say that the primary difference between Protestants and Catholics is the amount of authority which each group ascribes to the church body. Catholics see it as a reflection of the Divine Will of the Holy Spirit. (which is the point I was trying to make). Is that a fairer statement?