Moving Coil Transformers And Preamps...Which ones

Who is good and who is bad here? As I approach getting my feet wet for the first time with ownership of a possible Benz-Micro or Denon Moving Coil cartridge...I have to ponder about MC transformers and preamps. I have heard it said by some with more smarts and knowledge than I that certain ones "pump"! Pump??? What does this term refer to? I am curious because as stated earlier...I am just getting my feet wet with my first mc purchase. I have owned over 100 mm carts over the past 40 years from both ends of the price spectrum {$10 to $140 street...OM 40 Gold ...Shure V-15 VMR...etc. etc...} so am pretty well versed in phono cartridge attributes and pitfalls. I also just ordered a TCC TC-160LC preamp for $80 brand new which is designed to compete with the NAD PP-2. It has a Hi-Lo switch and features two sets of inputs for both mm & mc types of transducers. The rest of my modest system consists of an AudioSource Amp 100, Polk R-30 cherry speakers, Pioneer TX 5500II tuner, Pioneer PL-518 tt and PE 3048 tt. But what's all the noise about certain preamps making noise? Any thoughts or comments on this???