The RCBS is a great dispenser (I owned two and both were great, only sold them because I had to downsize) but I am leaning toward the Hornady for my next dispenser (very soon) just because I drink the red Koolaid.
By "dispenser", are you referring to the automated unit that trickles powder out until the desired charge weight is reached?
I use manual powder charge measures made by Dillon, RCBS and Lyman (the 55). I set the measure with the scale then take extraordinary steps to measure the powder exactly the same way every time and to minimize banging around on the bench. That banging/vibration packs the powder down in the measure and varies the charge weight.
If I had to pick ONE manual powder measure, it would be the Lyman 55. I have some adapters that allow me to use the Lyman 55 on my 550B presses but I use the Dillon automatic powder measure instead. The 55 has three separate chambers that can be set from coarse to medium and then a very fine adjustment. It is a very accurate measure.
Unless you are a high volume loader, it is far less expensive to stick with a manual powder measure and charge each case individually.
I've had good luck with RCBS and the much cheaper Lee "perfect powder measure."
For precision work, I still weigh every charge on a scale, then dump the powder into the case.
Example: Loaded 20 once fired Lake City 5.56 brass with 68 grain Hornady BTHP Match, primed with WSR, and 23.0 grains of AA2230 weighed individually.
At 100 yards, G.I. 62 grain M882 yielded 1 1/4" groups. The hand loads shot from the same rifle and rest gave 1/4" groups.
Intrigued by the results, I consulted the MILSPEC for M885 and the Army only demands 2 MOA at 200 meters for M885. Seems no one can center the "penetrator" perfectly inside the projectile. Hence the large tolerance for acceptable ammunition.
It is all about quantity or quality. If you can do both, go for it and GO BIG!