I have the Sun Valley EQ-1616D. It is used with NOS Telefunken EEC883's, Mullard EEC82, and Psvane 274 tube set which increases its total cost. But NOS tubes do elevate the sonics of of the phono stage.
I do not have a Hagerman. But I have another transimpedance phono, Channel D Lino C 2.2. The Lino 3.3, an upgraded version, is listed as Class A+ on Stereophile Recommended list FWIW. The Sun Valley plays differently to the Lino C, of course. The differences to me really falls along tube vs SS lines. The Sun Valley with the NOS tubes is much richer in the mid range, more bloom, a bit weaker in the bass, and generally more colorful. The Lino C is more neutral, in control, with more articulate bass. The Transfiguration Proteus is better on the Lino C than on the Sun Valley. And my ZYX Ultimate Astro is preferred on the Sun valley. My point is that the Sun Valley is consistent with Stereophiles ranking system. I use only the MM section of the phono stage paired with a Audio Tekne SUT, which is another cost added. The Fet based MC section with fixed 50 ohm impedance is ok.
Now there is a Blogger that I read and respect, Dr. John at Cheap tube Audio, whose review of the Sun Vally is less than glowing. He bascially questioned the rankings of Stereophile, which we all have done. His review can be read here:https://cheaptubeaudio.blogspot.com/search?q=sun+valley. He felt that his all mm/mc tube phono, Fosgate, is better. I, myself, am quite happy with the Sun Vally. But if you add up the cost of NOS tubes and SUT, it is not a 'giant killer'.