Investment isa

On listening to a local radio this morning an advertisement gave out a number to call for people who have lost money taking out investment isas. I opened one with Royal London in 1997. At the time the salesman said it would outperform by far the bank interest rate at the time. But within 18 months i got a letter to say that thy were scrapping it and i could either a. leave it until the new tax year when it would have made a small amount or b. take it asap and lose a similar amount. Because i was buying a new car at the time i took it out and took the hit. But this got me thinking today would it be worth looking into especially as the message said you wont need the original paperwork. Ive also had a 15 and 25 year endownments with RL and both didnt come near to what the salesman had forecast at the time. However , i do have the paperwork for those but only some of the scribblings of the salesman on what they were likely to bring back.