I had one last year for a couple of months. I wanted a sensible-ish car to replace my Megane R.S. and it came up locally with low miles. While it was a nice car and had plenty of toys (it was a Titanium X), I was disappointed with it to be honest. It never felt that quick, the engine was extremely muffled and, compared to the ST220 I owned a few years ago, it just felt a bit dull to drive. It had lost the response and feel that made older Mondeos such good cars to drive. Maybe a Titanium X Sport would feel a bit sharper, but I was left a bit cold. Was a shame, as I thought it might be quite a good car. I've had several Mondeos of various generations, but this one was my least favourite of all of them. Mine used to average high 20s MPG. The Mondeo has longer gearing than the Focus ST, which helps, but does dull the performance a bit. I mostly used mine for A-road/motorways which helped the economy I suppose. If it's a daily, I would probably just buy a diesel one. The 2.5T isn't really worth the extra fuel in reality. They did a 200PS 2.2 diesel which is probably the best option.
Mine got written off by a girl in a Fiesta after two months, but I wasn't really sorry to see it go in all honesty. If you're after that sort of car for £3-5k, I would probably go B6 Passat or E9* 3-Series to be honest. The Mondeo has lost its edge as a driver's car, so you might as well have the nicer badge and better quality interior. If you do want a MK4 Mondeo, watch out for steering rack failure. You have to replace the rack, pump, lines, reservoir if it fails, and it can get expensive.
I wouldn't buy another to be honest.