Personally, I'm not a big fan of Smith Machines. Smith Machines are a good idea in principle, but that's about it. They are designed to be a device in which you can still use maximal weights w/o a spotter, and still be safe.
However, on the flip side, it locks you into a singular groove of motion. That might be "doable" for a few exercises, but for most exercises, it just isn't - you simple don't move the bar in a straight line. I mean, you can get away with it (though I still don't like it) for OH presses, benches, shrugs, or DL. However, squats, curls, any sort of quick or O-lifts, etc. are all wrong. The necessity to work in a 2D (rather than 3D) plane of motion does more harm than the self-spotting capability does good.
It is relatively cheap, but that would also make me wonder about the quality of the equipment. When it comes to most home gym equipment, you get what you pay for. In this instance, I could see cables fraying/snapping, and many of the attachements (leg ext/curls, preacher bench, etc.) not being sold and being fairly wobbly.
What I would do would be to get a power rack (cage style) and adjustable bench. Stick the bench inside the cage, and set the pins at a height for any of your given exercises that you can just dump the bar. That gives you the self-spotting capability. You have to buy weights anyway with the other option, so that's not really an added expense. Most power racks have a chin bar built into the top, and you can many times a dipping attachment. Or, just buy a cheap extra olympic bar, and stick both bars inside the rack next to each other - do dips off of them.
Many of the other "bells and whistles" in the home gym are Ok, but surely not necessary. The leg ext/curl, preacher curl bench, and and fly station are really not needed. You can do single arm preachers on the back of your adjustable bench, and the other two...well, you just don't need.
The pushdown station is nice to have, but again, not necessarily needed. If you decided that you needed one, you could probably get an extra attachment for your power rack later on. Or, you could simple rig a setup off your power rack - hang a detachable pully off your chin bar. Run a length of cable through it that has a loop on each end. All you need is a steel dowel with a flat secion on the bottom and a loop at the top to stack weights on. You can make one of these pretty easy. Then attach your pushdown bar to the other end. Or, if you didn't want to do all that, use resistance bands.
That is the way I would go... Where is Bath? I'm in Cameron.
Hope that helps some...
Wiggy - MMA Training