I only recently discovered PDF24. I need this type of tool only occasionally, but when I need it, I need it, so I can't justify a monthly subscription to full Adobe Acrobat with all of its features, most of which I will never use.
Once you get the hang of it (which is true for any software), it's fairly intuitive. The ABSOLUTELY BEST feature is the OCR feature. I had two very long, unsearchable pdf's that I needed to review and I couldn't search them. I was able to use PDF24 to "OCR" the original to create (what looks like to me) a perfectly replicated (and now searchable) pdf. The original on one of them was like 52 pages, and I thought it did the OCRing very quickly. I've recommended PDF24 to friends.