Keep the Z4C or get a 135i?

[smith94]

Currently have a Z4C. Drive around 15-18000 miles a year. Although the car is perfect mechanically, it missed a service interval back in 2008 by four months or so. Despite accruing only 6-7000 between said service interval, the car does not qualify for a BMW warranty because of this.

In my 13,000 miles of ownership to date, the car has had new rear springs, rear toe links, a water pump and is currently in for a very small noise from the rear suspension at low speeds over bumps. I've also stuck some fresh rubber on, given it a service (7000 miles to go until Insp2) and replaced the discs and pads all round. I always maintain my cars as well as I can and don't mind doing so, however...

I could get a low miles 135i for £15-16k with an existing BMW warranty or simply put a comprehensive one on for £40 a month through BMW. A warranty is really appealing to me for peace of mind and the fact if anything big goes, I simply hand the keys over to BMW and wait for them to fix it! It'll cost me around £3,500-4000 to switch, gaining me more performance, 2 extra seats and a newer car, albeit without the looks and impressions of the Z4C (subjective I know).

I've done some big jobs on the Z4C which will mean if I keep it, it will give me some fairly inexpensive motoring for a while (touch wood!), however who knows what may happen and you're never too far away from £200-pricey bill from BMW, which seems to be the usual invoice for minor things up for replacement.

So, driving experiences please, a comparison between the two would be ideal - and if you were in my position, would you do the same?

Cheers,

Will

[smith94]

Well, I've already done 13,000 miles and have thoroughly enjoyed it.

Would a 135i offer the same feel even at low speeds? And is the additional £4000 worth it for one?