Thinking about an Audio Research PH5

Am I nuts? This is a $2000 piece that I can probly get a good deal on from my local dealer since I'm a good customer.My TT is a music Hall MMF9 that they sold me at a Big discount mainly because the MMF7 I originally purchased was defective. Is this overkill for this TT or will I be able to hear a difference. My current pre-amp was tweaked by an Agoner last year at a cost of $550. It's an Adcom and the tweak was noticable. The appeal of the Music Hall was the lack of constant tinkering involved. Is this a good move or should I keep saving for a better rig? My main amp is an Audio Research 150.2 and my main speakers are JM Lab Electra 926's. Thanks for the input!