I've read snippets of it from time to time when I come across it. Yes, it does appear to be quite difficult for someone trained in classical Latin (most of us), mostly on account of the vocabulary. Lots of seldom used, colloquial, and mundane words that you don't encounter often in refined language. I'd love to hear from someone who has studied it in depth.
The author points out his use of language in the first paragraph:
linguam Atthidem primis pueritiae stipendiis merui. Mox in urbe Latia advena studiorum Quiritium indigenam sermonem aerumnabili labore nullo magistro praeeunte aggressus excolui. En ecce praefamur veniam, siquid exotici ac forensis sermonis rudis locutor offendero. Iam haec equidem ipsa vocis immutatio desultoriae scientiae stilo quem accessimus respondet.
In other words, he first learned Greek and then learned Latin as an immigrant with much difficulty because he had no instructor. I'm sure the author is posturing to some extent, but it's definitely interesting prose.