"I listen to primarily Vinyl and I was wondering if anyone uses a phono preamp. Just curious to see if anyone has had any success. "
It appears the OP is masking if an outboard phonostage is "better" than his built-in.
The answer is for his particular price point Marantz, probably best just enjoy what you have, or look at something like the Schiit Mani for $150. SQ improvement might not be that dramatic assuming the Marantz built in is decent for a price point appropriate table/cart setup.