Sorry to chime in late, just a few thoughts.

I use Illustrator almost exclusively for my maps, by which I mean something like 99.8% of the time. I can tell you a couple of things though about it:

1) Considerable learning curve. I dinked around with this program a long time, building up my skills. There are still a lot of things don't do, and other things that folks who use it more than I do scratch their heads over. I like what I can do with it, but it doesn't come quickly.

2) Some things you will not do. There are some things that this program does not do. Period. There are a lot of cool effects in PS and other programs that I look at on other people's maps and say "Cool. Not something I'm going to do though." What it does well, it does well, but some stuff just isn't there. Or maybe I have not found it yet. Very possible.

3) Develop a style suited to the tool. Or not. I have developed a style that is (I hope) very well suited to this program, which actually makes working with PS harder for me because I get frustrated and just do what it isI was try9ing to do in Illustrator. This might be a bad thing, maybe I ought to branch out. Frankly, I don't know and I don't have the time at the moment to start from scratch. If I do get the time, I probably will, but if that is a factor for you as well, I'd skip it (re-read Number 1 above). On the other hand, I like the output, and so do some people here (again, I hope).