You'll probably be okay using it once a week. However, MXE is one of the most subtly and persuasively seducing drugs I've used. It's so hard not to ramp up use, because it really seems like it's perfect for every situation. You start to convince yourself that MXE will balance out whatever ails you on any particular day. You become very good at rationalizing its use.
After using MXE often, I started noticing that my thoughts and words were become more aggressive, more overly confident. It's really hard to describe how it changes your thought process, but you begin to see loops and interpret reality to confirm all of your thoughts and actions, both past and present. The confidence is empowering and nice in a way, but it goes overboard.
At the end of the month I began to get really paranoid and delusional about my health, something that is very uncharacteristic of me. Looking back on it now it seems absurd, but it was very real at the time. I was convinced that my apartment was growing toxic mold everywhere and it was the root of all my health problems. I thought I was developing bladder damage and even brain tumors. I was just way off balance.
The thing is, the changes in your personality are gradual but you don't notice them until you're way off kilter. Having a friend keep you in check might help, but you can't rely on it because they can't see inside your head, and by the time they report something is off you'll probably be deep inside the hole.
MXE was my favorite drug in the world at first, but it turned sinister toward the end. I started feeling really bad about myself, even though I would have thought that impossible when I first started using it.