Overall, I would say that my experience at Shane was good. It was my first teaching position and my first time in Taiwan. For the most part, I would say that the school is a bit more professional than some of the other foreign owned English teaching schools and certainly more professional than the English schools set up by local proprietors.
Shane does provide an initial teaching orientation, which helps in gaining your footing if you've never taught before. The pay is slightly lower than other schools, but as others have stated that seems to be balanced out by being part of a responsive and organized school i.e., your concerns are generally addressed and the admin in the head office do try to help.
There were three aspects which I did not particularly like. The first is with respect to taking days off. While the Shane program does have an organized request based vacation system, this does not necessarily work in practice. For example, all of the English teachers tend to want the same days off - usually clustered around specific holidays of times of the year. I found that admin tended to have first choice to take off such days for themselves and then tried to accommodate everyone after. The second problem I had, and one which I do not have a solution for, is Shane's "on-call" system. Every few weeks each teacher is "on-call" on their day off and must be prepared to go in to substitute for any other English teacher who happens not to go into their job on that day. Needless to say, this can be a drawback and - in practice - takes away one of your days off fairly frequently. If you are working for the money, however, this may not be as much of a concern. Lastly, Shane has a dress code. For men they require a button down shirt and tie. Although this isn't a huge issue, Taiwan is a hot and humid place and there are those times when you look at your non-Shane colleagues with envy for not being drenched in sweat.
Overall, a solid program, especially for those new to teaching.