Almost everything bought has proved pretty useful, but that's only because I read up on this forum before buying.
Roof topper has proved a bit of a waste of money for us. I hadn't taken on board how effective the auxiliary heater is, and with a good goose-down duvet we've not really found the need for the topper even in a (British) winter. (But if I was going to the Alps or to Scandi in the winter then I'd certainly pack the topper.)
Don't-leave-home-without accessories for us have proved to be:
- Lightweight (cheapo) internal windscreen blind - instead of the rubbish cloth VW one.
- Pair of levelling ramps. Use them more often than I expected.
- Two little wooden discs that drop into the T5 cup-holders to hold the spring-arms open so you can actually get a cup in with one hand!
- Outwell collapsible kettle. So dinky, but also practical.
- Neoprene multi-pocket wine bottle sleeves.
- Calitop kitchen shelf. We find it really useful in the evenings when the worktop is chock full of stuff.
- Woven Welsh wool floor rug (made to fit). Looks couth but easy to shake off dried mud and crud.
- Inka seat covers. Antithesis of the 'executive' look, but we like the practicality and they're decent value.
- Short strap that clips to dog harness and plugs into the bench seat belt socket.
- Really nice thick (Icelandic) wool blanket for the bench.
- Large dry-bag for stashing and compressing down duvet.
- Small bluetooth speaker. Just upgraded from crappy LS Hive to UE Boom 2.
- Bunch of 'spring coiled' USB charging cables, to avoid wires hanging everywhere.
- Cobb cooker. Love this, wouldn't be without for summer camping.
- Aeropress coffee maker. Already used one at home so not really a 'Cali discovery'.
- A bunch of plastic 'tupperware' style boxes that actually fit neatly on the various rear corner cupboard. shelves. Couldn't tell you the makes, I just trawled round hardware shops with a tape measure until I found ones that are just right.
- Thetford 335 porta-potti. Works for us - enough said.