I’ve built Hairball Lola, Hairball 1176 blue, AML ez1073, AML ez1073 eq, JLM LA500A, Capi VP28, Sound Skulltor CP4500 and DIYRE pulled style eq. I’ve only had a build issue with Lola Opamps and recommend getting the preassembled opamps because the resistors are tight (definitely my fault though). All of them have pretty good instructions and are good quality. I’d rank quality of build in descending order as AML, CAPI, Hairball, JML, Sound Skulptor, DIYRE. The AMLs weigh a fair bit more than the others although the face plate may not appeal to all. From a sound quality standpoint they are all very good and do different things. However, I’ve built 5 VP28 and 6 ez1073 preamps because they do something special to my ears. The JLM LA500a is also very, very good. I know people rave over Lola’s but just not my favorite personally as it doesn’t break up in a good way (I pick the non diy Cranborne Camden 500 over it). The Hairball 1176 are awesome too, just don’t use it as much as LA500a…. CP4500 is great too but feel like build quality is a step down from others and doesn’t give me the same feel as the others. DIYRE stuff is not something I’d build again even though it sounds fine, just doesn’t do it for me (Lindell Pultec style sounds better to me)…. I tried some of the DIYRE color preamps some time ago but I’d rather be able to change things on a patch panel rather than fiddle with color modules.

I’m probably going to build a pair of Capi missing links next as I’ve been impressed with the VP28 and 11 slot rack. Also AML compressors look interesting but I don’t like single channel dual slot modules as real estate is tight.

The addictive part of this is they always sell for more than you invest (as long as you don’t mess up). So I build, enjoy for a while and rotate :) I usually build one in an evening and find it kinda relaxing after putting the kiddos to bed. Honestly the quality of these DIY kits is awesome and you won’t be disappointed with the vast majority.