Old IBR vs. RAP for 2014 graduate, over $400K loans, current balance $520K

Hi, I graduated a dental school in 2014 with $400K, and about 7.5% interest.

I was on PAYE, paying about $1000 a month while the interest was $80 a day and $2400 a month. Basically, my interest accrued for the last 12 yrs and now the total balance is about $520K.

I went from PAYE to SAVE back to PAYE. I could have stayed on SAVE during forbearance but saw no reason to do so as I wanted to lower the total payment count.

I am currently on PAYE, but I understand I will soon have to switch to either old IBR or RAP.

I understand that the new IBR is pretty much the same as PAYE but I graduated in 2014 so I only have option for either old IBR or RAP.

I don't know what would be the better option between these two.

FYI, I got married last year, my wife is also in PAYE, but she graduated after 2014 so she has options for new IBR vs. RAP.

As far as I understand, RAP is 30 year program vs, old IBR 25 year program. I basically have to pay either 5 more years or 10 more years compared to 20 yrs of PAYE.

I make around $250K a year.

RAP is 10% of income per month so I guess that would be $2500 a month and the interest is waived. Not that it matters since I am paying $100 more than the monthly interest.

Old IBR is 15% of discretionary income, which I don't know how much or if it's more or less than $2500. And the interest accrued. With PAYE (10% of discretionary income, I currently pay around $1550 a month so 15% would be around $2250?).

5 extra year for RAP means $2500 a month x 12 months x 5 = $150K

old IBR I pay close to what I would pay for RAP (2250 vs 2500), I don't have to worry about paying $150K for the additional 5 year but the interest would accrued (not much though because monthly interest is $2400 so that's only $150 a month)

Do you think old IBR is better for me?

According to the counter, I have made 125 payment out of 300 and still have 175 more payments to go, but the total number would change from 300 to maybe 360 payments with old IBR or 420 payments for RAP.