Most of the major kits Spud amp, Transcendence OTL, Bob Latino Dynaco clones or Bottlehead amps have a quality end product and a very good support group forums around then and you couldn’t go wrong with any of them depending upon your determination and patience.
The big question is what kind of amp do you want to build and what speakers are you going to drive with it.
For simplicity and just starting out to learn the Spud amp is supposed to sound great and is really inexpensive to get into. Not a whole lot of power and is more of a gateway amp into the next level