Replying to Fks rant (help needed)

so i have been using fks 155 for 2 years in the park and it has been a miracle.
every other binding i had would just collapse in weeks or just release when not needed.
i weigh 160 lbs so i set my din at 8. My bindings released maybe 3 times last year. I ski pretty hard and about 80 times a year.

because i had used them alot (4 years of racing before putting them on my twins) and because i thought they were getting a bit loose on the heel part, i decided to buy new ones.

i was thinking of buying 180s because they dont make 155s anymore but the guy at the shop told me it wouldnt be good to set my din at 8 on those bindings, so i thought, fuck it lets go with the 140s.

i just tried them today and they would always release for nothing. every time i would lock with pressure for a blind 270 out my ski would pop out.

So i was thinking.. the heel part now moves around easier, so i dont know if the release pattern has changed because of that. The 140s come with the small toe piece, and got me thinking if it was a shitty part.

now im contemplating this situation and wondering if just blew away 400$ for nothing.

halp me ns... does the 155,180 toe piece on the fks make a real difference?