Casting can become an obsession unto itself. Often I have been bitten by the "I want to cast" bug and found myself in the garage for 5-6 hours making up a few thousand bullets for friends.
Casting is easy, the lubing part takes a lot of time. I have tried the tumble lube bullets/process but I really hate the smell of the stuff, the complications in reloading (leaves crap in the seater die) and the smell at the range of the burning lube. To each his own I guess.
I started casting about 7 years ago and have acquired more than 100 molds so far, actually have a 6' filing cabinet full but I have started to downsize and get rid of the molds I no longer will ever use.
I started out with Lee single and double molds and struggled with them for about 1 year before I finally took the plunge and bought a 4 cavity Lyman 429421. Obviously production increased with a 4 cavity but the mold is heavy as it is iron and sometimes the bullets would stick.
I finally got in on a group buy on the castbullets site for a 200gn swc .45acp 6 cavity custom Lee mold. Holy crap what a difference between there 6 cavity and there one/two cavity molds. You can cast with this thing for hours on end and not have your arms/wrists hurting from the weight. Open the mold and the bullets literally want to jump out. In fact you have to have a damp rag beside you and cool the mold off a bit once you get going.
My own personal experience has been that most Lee molds are under size as well as most Lyman/RCBS production molds. The throat sizes on my .44 Magnums are .431 and .432 so I need a .432 bullet and not a .429. I usually have molds made now that I specify the correct measurements and get in on the Group Buys on Cast bullets website. Makes a world of difference when there is no leading in the barrel and the same accuracy at the target as jacketed bullets.
As far as the 2000fps myth as the limit for cast bullets, that was in days gone by when people were using 50/50 beeswax/grease and the wrong size bullet. Now with heat treating bullets in the oven and modern lubes there is no problem using full power loadings in my 30/30, 30-06, .303 and 8mm rifles.