What makes a Fox body better? Your opinion, what you like.
There are less ways to screw up going fast in an LS1 combo than a Fox combo. Generally speaking and of course in my opinion only, the era of the fox body was the begining of the aftermarket. It was open game for aftermarket companies and a learning curve for everyone in their mad dash to bolt something onto their car. With this there became a plethora of different views of what worked best and even now the aftermarket is so big for ford parts there are a million different things you can do to "customize" your stang, and in that, there are a million different ways you can screw it up. This also goes into the looks/stylizing catagory as well.
There is also such a large range between what people are after as far as "Fast" or speed goes, and what a person is willing to do to get there.
Compare all of that to the total options for an FBody and you'll see what I mean. By the time the Fbody market really got going we had started to use the internet more and more, understand tuning and also the utilization of chassis dyno's when picking combos. Don't get me wrong, I'm not saying there aren't alot of choices for Fbody guys by any means but in comparison, I believe there are alot less ways to screw your combo up. An LS1 is also a good base to start with.
That is my view of the downside of choosing a Fox.
On the other end, since the aftermarket is so vast, it's generally cheaper and easier to find new and even used parts in good condition. You'd also be starting of with less weight which is of course a big help.
If you were to choose a Fox, I cannot stress enough that you find someone who is accomplishing what you want to accomplish, the way you want to accomplish it and listen to them and only them. If you don't you'll end up with alot of good parts that don't work well together. If you are insistent on picking the combo yourself, than be careful where you get your information, because there are a ton of different opinions.
There are a ton of reasons for choosing one over the other, but it all boils down to which you would rather build.
EDIT: Holy Crap, I didn't notice the date!