Schiit Mani vs Atoll P200SE Phono Preamp

Is there a breakin period for phono preamp.

i have a Rega P3. You consider that entry level? 

The Rega 3 is a solid entry-level table. It will work well with a decent MM cartridge and the Schiit Mani. Leave the Mani on permanently if possible and will sound best after a few days.

I guess in this circle anything under $2K is considered entry level... But that aside, if you decide on the Schiit Mani, go the extra mile and get a Swagman linear power supply for $125 and you'll have great sounding preamp with enough flexibility to accommodate a decent range of MM cartridges.  

I bought the Atoll P200SE and received it yesterday. 
How long is the breakin period?

I can buy the power supply. Exactly what do I plug into it? ...the TT and phono preamp only?

Power supply replaces the wall wart that is supplied with unit.

P3 is a fine table in its price point. Performance expectation should based on your entire system. LPS is the least of your nervosa.