What I'm afraid will happen (and it will) is how impressed I'll be with your M3 and how disappointed you'll be with mine
your M3 is looking reallly good!!
For the e-fan, I have been running my SPAL for many years with no problems. The only thing about them is fitting them can be a bit of a pain. In the sense that in order to get close to matching the air-flow of the OEM mechanical fan you really do need to get the high performance SPAL, which has a big motor which means you have to offset the fitment so it doesn't hit the waterpump nut. Bimmerworld kit is what I used and I think it's the best. I would not use their straps as they're lame.
Essentially this kit
High-value and effective electric fan conversion - easy to install!
www.bimmerworld.com
But with this fan
Premium-quality electric fan providing reliable cooling whenever and wherever needed
www.bimmerworld.com
With these brackets:
We offer stainless steel brackets for mounting a 16 inch SPAL fan on an aftermarket BMW radiator. Get your BMW performance parts from Condor Speed Shop!
www.condorspeedshop.com
*you will need to drill onto the very edges of whatever radiator you choose to mount those brackets. You'll have to mock it all up to ensure the fan motor doesn't hit the waterpump (you'll at most be like 1-2" away).
I used a CSF all aluminum radiator this time around from FCP. It's worked fine. Last time I used a Z3 S54 radiator, also worked fine. It is much easier to install all of this having the radiator out of the car and being able to mock it all up and measure, drill and mount the fan carefully. After all of that, I was able to mount brand new OEM plastic shroud over the SPAL... it's almost a perfect fitment and most people won't tell it's there.
That said, if you want to spend money, you could just get a full Zionsville kit, which seems nice. Probably a bit overkill. And of course doesn't use the factory coolant reservoir. I don't have much experience with their stuff but they've always been considered one of the best.
Zionsville Autosport - BMW E36 Competition Cooling Kit Fits: BMW E36 1998-99 323is, 1992-95 325i, 1992-95 325is, 1996-98 328i, 1996-99 328is, 1995-99 M3, 1994-95 325i Conv., 1998-99 323i Conv., 1996-99 328i Conv., 1998-1999 M3 Conv.
www.zionsvilleautosport.com