I'm sure it will be fine, maybe a bit more noisy than a western jet though. I believe some 154's have hush kits and some don't.
As an alternative there is a fast train which serves Peter and Moscow, I believe it's called the Aurora and journey time is about 5 hours. This is probably quicker than taking the plane, getting to the airports in and around Moscow can take a long time.
There is also a luxury overnight train called the Grand Express which I've been meaning to take for years but schedules never fitted. It's like a hotel with private cabins. The last time I looked, which was about 2 years ago, it was about €100 each way, like everything in Russia it's probably a lot more expensive nowadays....