I've got just about every die maker represented on my bench. Lee, Hornady, RCBS, Redding, Forster. Every time I thought one wasn't doing the job, I tried a different brand and in many cases found that the issue wasn't in the die but the brass itself. Hard to make straight ammo from inconsistent or "banana brass".
For the value it's hard to beat Lee Dies. Good sizing dies although not as well polished as the more expensive. The Collet Die is great but be prepared for some vertical marking on the neck (that doesn't harm a thing). For absolute accuracy, without going to Wilson Dies, I find Forster to be the ticket. Excellent quality and no "Bend Over" pricing.
As for which die for which caliber? Only buy the high end dies for the calibers where "dead nuts" accuracy on finished ammo is required. For "Shooting Ammo", the Lee's work just fine and leave a lot of shekels left over for essential stuff.