St. Petersburg to Helsinki has anyone done it?

[relevart]

I am taking a Russian river cruise from Moscow to St. Petersburg. I am using frequent flyer miles. They cannot get me a flight on the day I want, or the days around it from St. Petersburg to Helsinki, where I can use my frequent flyer miles. The flights from St. Petersburg seem very expensive and hours long for the hour flight except on Pulkovo Air and I have read it is a rather iffy airline. Have any of you rented a car, taken a ferry or train?

 

Thank you

[tiggrrr]

I would recommend by train:

 

http://www.vr.fi/heo/eng/ita/ita.htm