I've been using logic for a few years now, and recently had a tinker with SX. I really like SX visually and it is a very powerful program, but for me logic has a better environment, ie. it is less cluttered. When I use cubase, i feel like i'm forever having to move things around, and i really dont like to cascade screens as they become very small and i hate having to constantly scroll around.

Logic is organised so that each part of the environment is sepereated and each number on the number keypad corresponds with a seperate screen, eg. 1 - Arrange window, 8 - track mixer etc. (maybe you can do this in SX, i;m not sure)

I also love the ESX24 sampler, by far the most powerful and quality sounding soft sampler I've come across, and the emagic virtual instrument are good also.

As far as the conversion to Mac is concerened, i was planning to buy a mac anyway. I've used both PC's and Mac's for a while, and there's a certain quality of sound the mac produces that to me seems of a higher standard, also i've had PC reliability problems in the past that have really got on my tits.

i appreciate there are many SX and cubase users on the forum and i do think it is a quality program (particularly for audio-visual projects), but logic is my first love. so there...hehe.