I would barely be driving on the highway. Maybe once a week max.
The SRT-4 just suits my needs. It's cheap and very fast for the price. I want something with low miles that'll last, and I can't get that from a Mustang GT in my price range. Parts are dirt cheap, and it can be made really fast for relatively cheap. 300 horsepower on the stock turbo can be had for under $1,000 and if you put on a big turbo these things can make some big numbers.
To add significant power to a Mustang, you're gonna have to supercharge it. $$$ that I don't have. A $150 wastegate for the SRT-4 will give it a big power boost, with a few supporting mods if you want to take the boost a lot higher. I think the record is around 330hp and 350ft lbs torque on the stock turbo. When the car only weighs 2900lbs, that'll move you.
Sure RWD would be nice, but I don't really need it. There are guys who run 11s with their Neon "turds". If I found a good deal on a 5th gen Mustang GT of course I'd jump on it, but they're expensive, and I don't really want a 4th gen.
And again, I'm not even considering that Eclipse. I just thought it was funny.