I also hyperstimulated after one pessary - picked up immediately as I literally went from nothing to a continuous contraction in about 15 min! Induced at 42 weeks.
There was no way I would be induced again second time around (was aiming for a vbac though, so they couldn't have used the pessary on me again). Was paranoid that I wouldn't go into labour naturally.
I took evening primrose oil, orally and vaginally. Did lots of bouncing on ball to get the baby into a good position. Went for long walks with my DS in his pushchair. And agreed to my first sweep on my due date (just the way my appointment happened to fall).
It was a good sweep but I didn't have high hopes - I'd had 3 sweeps with DS to no avail! Started having a show the next morning. Went to my regular yoga class anyway. Then started feeling funny in the afternoon, turned into labour after my toddler went to bed. My dd was born the next morning - a vbac and a good experience (even though there was some foetal distress too).
I was contracting like mad though, from quite early in labour. As in, went to hospital at 5/6 contractions in 10 mins and was only 1-2cm! Nearly cried! But then progressed to 10cm in an hour and a half, contracting madly all the time (hence the foetal distress).
My unscientific theory is that that's how I contract/labour - as in loads of contractions - which leads to meconium in the waters, foetal distress, etc. I think it explains why I hyperstimulated immediately first time around. No doctor or hcp has confirmed this - just my hunch!
But a sweep really helped me and I'd consider it again (early stages of pregnancy with dc3).