I have now gone through the book.You have mentioned that errors are not only technical (which are probably easy to fix), but also conceptual. Can you pinpoint to some of the conceptual errors?
It has technical errors, but gee so do other textbooks I read - its in fact a good exercise picking them up. It is also too cumbersome in places - I can find more elegant explanations to replace some of the long calculations he does.
But actually wrong - not so sure about that. Its advantage is exactly what I said. A professor that posts here has said, and IMHO its totally true as far as reactions go - it was mine when I learnt about it and had a very deep effect on me - when he teaches Noether's Theorem there is stunned silence as its import sinks in. This whole book is built around that famous theorem at a level 2-3 year undergrads would understand. It contains nothing new - but being exposed to exactly why the Higgs theoretically was thought to exist and other areas not usually at the undergrad level is very uplifting. And for many that genuinely likes theoretical physics seeing the importance of symmetry early on is - well uplifting.
It's like Landau - Mechanics. It contains nothing new - but is presented in such a brilliant, different and concise manner you sit in awe - all physicists should study it. Of course this guy is nowhere in Landau's class but like Landaus book, its different perspective is so inspiring.