I had two student midwives during my pregnancy and delivery with very different experiences.

One attended a lot of my midwife appointments during my pregnancy and then she came and attended me with the midwife while I laboured at home, she also followed when I had to transfer to hospital and then attended my postpartum checks at home. She was lovely, very gentle, gave me plenty of space, followed my lead and the lead of my midwife but also brought some extra assistance, support and advice when she could. It was great having her around.

Since I had to transfer to hospital my midwife and the above student had to hand over to the hospital midwifery team after they brought me there.
So during the later part of my labour and the delivery I had a different team. A nurse, a midwife and another student midwife. The nurse and midwife were absolutely amazing and I am still amazed by how well they cared for me and held everything together. The student midwife at the hospital was a pain in the arse. She just hung around often getting too close and being in the way and she was always super keen to do internal examinations and kept asking if she could do another one (she was actually pretty brave for asking I guess, but no not what I wanted at that time). I let her do one and it was the most uncomfortable internal exam I've had, so I guess she needed some practice but I didn't want it to be on me. Eventually when everything went pear shaped she just kind of shrank back against the wall while the nurse and midwife worked their guts out.

Admittedly it was a really different situation with the two student midwives and the one who attended me at the hospital may have been a lot more pleasant had things not gotten so difficult or maybe even if I had met her earlier on.

In general I agree with Teeki, my better student midwife was supportive but they were both there to learn midwifery, supporting me was not their primary reason for being there.