If you're a materialist, which sounds likely to be true given the available evidence, any claims to the supernatural are disqualified by, for example, the Sagan standard.
This is the argument of quacks and charlatans (including the meditation charlatans aka "gurus").
A quack will always argue to ignore criticisms of his snake oil and just try it for yourself and find out.
Evidence is not personal, it's universal.
Denying universal facts and saying this is true for me is a position of a closed mind. You are being invited to prove facts, not just assert personal truths. It can't be more open minded than that.
Your attitude makes it inherently impossible to prove a non-materialistic position as you refuse to investigate for yourself. Far from strengthening your ability to find the truth you are simply closing your mind to other possibilities.
I know there are studies about the efficacy of meditation in certain scenarios, which is why I do it. But that falls short when you start claiming supernatural states of mind.
> Your attitude makes it inherently impossible to prove a non-materialistic position as you refuse to investigate for yourself
Personal attitude shouldn't be relevant when you're talking about evidence. One of the main attributes of evidence is precisely that it is objective and not personal.
It's like saying "I believe in X. I won't accept any evidence against X. Since Y is against X, Y doesn't exist"
This means you'd never realise X was wrong in the first place.
If you think testimonies are evidence, and are making appeals to antiquity/tradition, you just aren't thinking in an educated way. None of that is "evidence".
I'm open to accepting non-physical evidence if you can prove it exists. If you can, that would be very interesting, but it's likely that you can't. Again, anecdotes and tradition aren't evidence.