recomendation on a power conditioner

i dont think i have one but a few salesmen ive talked to recomended one for surge protectionand have also stated that it would improve the overall sound of my components.they especially recomended the shunyata but i had looked into the monster cable conditioner mainly because of price. i cant actually quite understand what they do.

thinking about purchasing a demo shunyata hydra 4 from a local dealer. Contacted shunyata a nd they recomended hooking up an integrated amp to it. admittedly im new to this so i think i am going to try it out. i have a musical fidelity x-150 along with a naim cd5x cd player
im going to start off with. the turntable and phono stage
ill add in later cause i dont use them as much