Owners report that switching to D'Addario 11's improves tuning stability and intonation on models with Bigsbys and floating bridges.

Upgrading to TV Jones pickups is considered by some to improve the cold tone and sustain issues of the stock pickups.

Owners find that replacing Gretschbuckers with actual FilterTron or HiLoTron pickups significantly improves tonal clarity, offering a less muffled and dark sound.

Locking tuners are a common upgrade, often leaving holes on the back of the headstock, but not affecting the front appearance.

The 5120's neck is thinner than expected and similar to the Epi Casino, but lacks access to higher frets compared to the Epi 339.

Blacktop FilterTrons from the 1970s are described as bolder and less crisp compared to true FilterTrons, which offer a more defined edge in sound.

The floating bridge can be challenging, and the strap screws may require locking washers to prevent slippage.

The 5120 is prone to feedback when used with a Vox AC 15, but can be controlled with practice.

The Gretsch 5120 is favored by Beatles enthusiasts for capturing the jangly, vintage tones reminiscent of 60s rock and roll, aligning with its semi-hollowbody construction.

An owner notes satisfaction with TV Jones P90 pickups, suggesting these enhance the guitar's versatility for various music styles beyond stock capabilities.

Some owners find leftover tuner screw holes on the back of the headstock due to upgrades, which can be visually minimized with filling techniques.

The headstock often has stickers covering the Electromatic logo, which can leave residue when removed; lighter fluid or naptha are recommended for cleaning.

$450 is considered a solid deal for a modded G5120, whereas stock models typically sell for around the same price.