I have purchased both form factors, and personally they are both very close in my opinion as far as use.
If your looking for a "cheaper" sight, I probably would suggest the Red dot "scope" looking sight simply because lower budget holo sights some times get poor reviews on being able to see the dot during day light outdoor shooting.
I personally like the holo type sight for faster target acquire when using pistols and timed events but my wife likes the red dot but with a smaller objective lens so she doesn't have as large of field of view. I first started out with a Bushnell trophy red dot that has both red and green with 4-5 recitals since she has poor eye sight and tends to switch eye dominance.
To be fair, your probably going to like something different than me, and the best way is to head to your sporting goods store and look at a couple just to see what feels natural to you. Take a look at some of the low powered scopes if your going to be shooting 100 yards ever.