Just get the 550 and get it over with. I`ve loaded on one since the 1970`s and would have nothing else. If your going to be loading large volumes of 1 cal. the 650 might be a better choice, but unless your going to be loading several 1,000`s of rounds of 1 cal. I would recomand the 550. I would also recmoand that you get Dillon dies if your going to load handgun ammo, especially if you load cast bullets, they are more than worth the $50 they cost because you can take them apart and clean out the bullet lube without takeing them out of the press. I know 2 people that reload on the Hornady progressive presses and both use Dillon powder measures on them. Today there are alot of good presses on the market, but I still think that the 550 Dillon is the best for the money.