Fitted a 'Horizon LED' interior upgrade kit, which cost £24 including delivery, after a discount code on their website.
Not a lot of money, but a few things have annoyed me about it. Here's what you get, quoting from the website:
E85 & E86 Models (x10 Bulbs)
x1 Front Courtesy Light
x2 Front Map Lights
x1 Glove Box Light
x1 Boot/Trunk Light
x1 Centre Console Light
x2 Front Footwell Lights
x2 Festoon Number/License Plate Lights
I started with the 3 interior courtesy lights. The original bulbs are small enough to be replaced by simply removing the surround from the roof, but the smallest of the LED bulbs (which I assume were correct - no instructions provided) wouldn't then fit through the gap without taking the whole enclosure apart into individual pieces; not hard, just a pain.
Then did the boot light - easy to do, bigger OEM bulb so used the bigger LED bulb in the kit (of which there were 2 provided).
On to the number plate lights - these had the same oem bigger bulbs as the boot, but as I only had one bigger LED left I used 2 small LED lights.
No light in my glovebox, despite searching around with a torch
Didn't bother changing the center console light (where the CD changer is) as I never use it and didn't even realise a light was in there.
This then left me with one small and one big LED bulb, which I used in the footwell lights - bigger bulb on the drivers side.
After all that, I'm left with 2 long LED bulbs with a metal contact at each end similar to an inline fuse, haven't a clue where they might fit.
Now I read their website again, I think the 2 supplied 'large' LED bulbs were meant for the footwell lighting but this size will clearly fit other housings too - so coupled with the random 2 left over bulbs the kit as a whole is a bit confused. Better off, and possibly cheaper, just to buy a handful of both type and experiment with what fits where for greatest light output.
Very light weather at the moment so the car isn't really being used at night, but the interior is far brighter than before (and the boot) when unlocking and getting in as a test - so I'd recommend swapping as a general idea but not necessarily this kit.