Here's my view on denominations:
I think it's good for people to try to find a church that makes the most sense to them. I don't think it is necessary to be a member of any church to be saved but it can help tremendously on keeping a person on the correct path. I don't think the age of a church means much. Satan has been around from the beginning of time and before Christ became flesh and after Christ was executed and resurrected. If Satan has any will to infiltrate a church he would've definitely been there in the early days too. If anything the oldest churches have had way more time for Satan to try to inflict misery and confusion and stumbling blocks on their members.
No-one can say even the Catholic church is free from that. As the years have proved, even the Catholic church has had its problems with sinful people committing vile and heinous things while giving an impression of being on the right track. And these problems are still there, often covered up by the fellow believers. I don't think I'm wrong in saying that every single denomination has had these problems so I'm not outing Catholic church for this. I am just saying maybe we shouldn't put different denominations on a pedestal too high, because the higher the pedestal is the longer the fall is when things come crashing down - and surely no church is immune to that, not even the Catholic church. I might not even dare to think what might've been possible for a church to become had Satan been able to inflitrate on it that early. There would've been a couple of thousand of years time to slowly rot things within the church. That said, I believe that even in that situation the church would still have its merits as long as faithful believers still existed there. All it really needs is two or three people gathering together in Christ's name for Christ to be among them - just as Jesus himself said.
Now, I will agree that being the oldest one out there certainly has positive aspects too. Often when people are arguing about a thing, it has already been argued since the beginning and the church history and its traditions may very well already have the answers.
Arguing for or against different denominations has one big problem: the core of the Gospel can sometimes be forgotten when people are arguing about trivial things. I don't think you have to have the perfect understanding of King David's history or what the Nephilim are supposed to be to be saved by the blood of Christ. The denominations are often about that - they agree one the core but they have different understanding on the rest. Then they'll argue about the rest, and even become bitter towards each other, and forget why they have become believers in Christ in the first place.
Here's a song that kinda illustrates my point:
It's
Trivializing the Momentous, Complicating the Obvious by my favorite band
Tourniquet.
It's a Christian heavy/thrash/progressive metal band from the US.
Here are the lyrics:
A difference of opinion - we agree to disagree
but you have stopped talking with me - now you're talking at me
Pre-trib, post-trib, five point, no point, heal me, slay me, free will, no will
as our common ground leans to the moribund
Delighted - devastated - dilapidated
Impressive - insightful - insane
Enchanted - enraptured - embalmed
The narrow path you're on will soon become a balance beam
and to always win the war of words is where you get your self-esteem
The message of his word says come to me as a child
but when I mention to you, you say his word I've defiled
"Enough about you talking about me - Why don't I talk about me for awhile"
"Yes, but the point is..."
"See here - The polemical literature states clearly that sufficiency of attrition is not enough for even the penitent of confessor to overcome the antidisestablishmentarianism of one's dispensationalistic concept of theistic determinism"
"No you..."
"The loftiness of my vicissitudes precludes the fact that we simply cannot see eye to eye"
"Are you sure you're not double minded?"
He came to set the prisoner free
A message of simplicity
"Pre-trib, post-trib, five point, no point, heal me, slay me, free will, no will
as our common ground leans to the moribund"
As if different understandings of how or when tribulation happens or how many points you follow on Calvinism or if you have free will or not, or whatever other subjects there are to argue about, makes any difference on the core of the Gospel. Yet sometimes people seem to lose their common ground when debating all of that.
Now, I don't think that kind of a debate is bad and I think it's only natural for people to try to make sense of what they believe in, but sometimes enough is enough and things can get too far.
"He came to set the prisoner free
A message of simplicity"
Jesus himself said we should become like children to enter the kingdom of Heaven (Matt 18:3). Jesus was glad to let children come to him for prayers and blessings. Those kids certainly didn't understand all the details of how things work. The disciples even mocked the parents who brought their children to Jesus (I think it was because the disciples thought the kids are not old and wise enough for that). But Jesus went as far as to say the Kingdom of Heaven belongs to people like them (Matt 19:14).
The message should be that simple; Christ is here, let people come to him. No more, no less.