Love my indigo hakama. I have the heavy weight cotton and its lasted 7 long years. All I have done is replaced both knees(make sure you a tailor capable of pulling off such a feat. You cant tell mine were patched. BTW I found the material to patch the knees at the rag shop and it didn't need to be dyed to match the hakama).The koshita is getting worn and is need of fixing.
The downside, they are expensive(but they are top end) and you have to deal with the smurfing effect. You will spend the 1st couple of weeks dealing with the blue dye wearing off on you, your gi, your partners gi, the mat. The dye needs to be set in the fabric so make sure you have done this and your partners will thank you for it. Also the iwata is cut different so folding it is a true test of patience and skill.
Bujin makes an excellent hakama. As always go for the heavy cotton. In my experience, it holds its lines better than the iwata, and much easier and forgiving to fold. My bujin was a hand me down. Both knees were replaced 2x and the koshita was repaired using the bujin koshita repair kit they offer.
It is now retired, it was stepped upon and ripped down one of the side seams and the koshi had developed a horizontal tear. Its beyond salvage and is living a much deserved retired life. Just cant bring myself to throw it out.
I prefer the heavy weight cotton. Its harder to keep the folds and fight the wrinkles, but the feel is an experience.
No experience with the cotton/poly blend.
Dislike the poly hakama, But it is cheap and holds its folds/lines. Very low maintenance, weighs next to nothing.
I hope that helps.