Personal retreats are very useful in gaining more self-reliance, rather than reliance on a teacher. But we don't encourage people to do personal retreats unless they've had experience in doing teacher-led retreats. Then they will already know some useful ways and methods to deal with the difficulties that arise during a retreat, because in a personal retreat you're largely your own teacher. It's certainly good for developing more self-reliance, and really using the techniques to deal with the Five Hindrances as they arise in the practice. It'd also be good if you had some confidence in yourself. We don't encourage you to do anything longer in time length than what you've already done with a teacher.
We also would encourage getting some beneficial readings, nothing too "high". If you get something too high, then a lot of idealism may arise, and discouragement. Take some encouraging readings with you so that you have at least some Dhamma teachings there that you can refer to when you can't actually be your own good spiritual friend. The last personal retreat I did, I selected two or three Suttas that I felt had to do with what was happening in my life at that time, which may come up for me. They were very helpful, just to remind me "Okay, this is what the Buddha asked us to do with these particular situations."
The dangers of doing a personal retreat are that if you get into some difficulties, particularly with concentration phenomena, there may be some fears arising. We have to know how to balance these types of things and get our practice to a safer place. Remember Compassion/Lovingkindness, the basic practice to develop. I believe it's important to know confidence inspiring objects of meditation before you go into a personal retreat because sometimes, as I asked you at the beginning of the retreat in the talk, "How would you feel if you're sitting in the hall alone, walking in the walking tracks alone, not able to have support from others?" So, being able to gain support from our reflections on the Triple Gem is very helpful, so that we don't feel so alone. Reflect that others have done this before.
I would suggest that you start out with a short one first. A shorter one, three days, before you try a ten day one. See how it goes, if some difficulties arise, ask questions of a teacher about what to do in that situation, and then gradually extend it. But all of you have had quite some practice, so probably you could try a personal retreat, especially if you're in conditions and you can't come to a teacher-led retreat. It's very helpful to go inward for a time.