Lay on your back with oil dripping in your eyes trying to precisely set a main bearing doesn't necessarily give good results.nor does it lend itself to a leak free oil pan.Torquing is a pain too.its fairly easy to pull the engine especially if you use some sense,like installing decent connectors in the headlight harness.One caveat,I enjoy maintaining the car as much as driving it..On an annual everything gets checked,leaks fixed,improvements made...
full disclosure,I push mine pretty hard too