I won't suggest any particular cars, but just a few thoughts on criteria... Are you sure you want a single "everyday" car? £45k on a second hand performance car is going to buy something that costs a lot if something goes wrong. OK, so general reliability will give you some idea of the risk, but something can always go wrong and take it off the road.
I'm sure you've done your budgeting, and I'm sure you know all about running costs, so I won't bother going there. However, there is also something else to consider, something I've been seriously considering for a while now. Where do you use all that performance?? If your roads are anything like these around here, you open it up on a backroad, cut nicely into a tight left hander and disappear up some horses backside, or suddenly find a bicyclist in your passenger seat. The roads around here are infested with bicyclists, horses, hikers and God knows what else, all standing around in the middle of the road as if it's a blooming car park.
For all the time I get to actually enjoy the power, I may as well be driving a Mondeo.
When I go to change mine (perhaps next year, it depends on the Scimitar project) I am now intending to spend a little on a cheap daily drive, and put something decent in the garage for trips to the 'ring and such.
I suppose it depends on if you have a garage available, but for £45k my thoughts would on something like a a Sagaris or a 997 C2S and, I dunno, an ST220 or something as a daily drive.