Do you believe the Earth 6,000 years old, or 6 billion years old? Do you believe in Evolution or not?
I don't believe it matters so much what you believes with this - I am far more concerned about why you believe what you believe.
If someone has come to the conclusion by searching through scripture that the Earth is way more than 6,000 years old (aka, the gap theory, etc) - and they came to this conclusion based on their search through scripture first, and then found that there was science to back it up - to me I'm not as concerned - even if they're wrong - because they are putting their foundation of belief in searching through scripture and trusting in God first.
Likewise if someone believes that the Earth is around 6,000 years old because they studied the bible first, and then finds science that backs this up too - even if that ends up being wrong - I'm still not that concerned about it...
However if someone comes to the conclusion that Evolution is true, or the Earth is more than 6,000 years old (or conversely that the Earth is young and evolution is not true) - because primarily that's what the men they trust in say - and then they try and look for scripture to twist and back this up - I am very concerned. The reason being - that their trust and faith is based more on what man says and then trying to make Gods words fit than the other way around.
I acknowledge that the search for truth takes us all on various journey's and experiences, and we all are going to be wrong about some things (me probably more than many!)... but in the end the main concern for me is where is our faith and our search for truth primarily based?
What I tend to find (I admit - in my small limited world experience) - is that most people I talk to regarding the belief in evolution have their faith based first on mans scientific discoveries over God's word. That to me is already a warning sign and an indicator - because I'm looking at the why, not the what. Whether they are right or wrong - I see dangerous times ahead, because deceivers are very good at their job, and we know that there are some deceptions so good that if it were possible, even the elect would be deceived. (Mat 24:24).
If someone puts their trust in man first (whether that be evolution, or young Earthers) - will they trust in a false messiah too because they are swayed by man's logic over scripture?
FWIW - I much prefer to stand before God being wrong and throw myself at His mercy because I believed in, but had an honest misunderstanding of His word, rather than because I put my trust more in man to the point that I doubt God's own words.
For me personally with my search - I have found scientific evidence that supports both old, as well as a young earth. I have seen scientific evidence that supports evolution, and also dismisses it. What I choose to accept is based more on what lines up with God's word. There is more than enough evidence to prove that much of science is biased, and flawed, and man gets things wrong. Man has disproved the bible, and then being exposed that they were wrong about their disproving countless times before - that I know where my trust should primarily be.
There is so much in scripture that proves I can trust God in the things I know for sure - that I choose to trust Him in the things I don't know.
From that perspective, I am happy to have discussions with anyone on this matter if they trust God's word first regardless of what they believe (if it's a discussion and not an argument) - but I'm seriously not interested in discussing this issue with people who put trust in science first - as I fear their is a much bigger problem that needs to be addressed than the age of the earth, or the aspects of evolution.
(In saying this- it doesn't mean I don't value scientific discoveries - but they are a far distant second to what God says first for me.)