RX8 if you don't mind fuel costs. It handles like its on rails, is proper luxury inside, seats 4 adults quite easily. Unique rotary engine, which if you take care of it like it should (i.e. using the whole rev range when warm & regular oil) it will last a long time. May not be the fastest car stock, but if your budget is £25, you can buy them new or 1 year old for around £15k, and add a supercharger or turbo (or increase the displacement). BTW I have owned one for 7 months, and is probably the best decision I have made. No regrets.
Always good to have a wide variety of opinions, but why with a budget of 25k, would he go for a car that is easily available for 8k?