[voltagex_]

Just off the top of my head:

* One manufacturer and one manufacturer only of the parts for my particular wheelchair (A Quickie GTX by Sunrise Medical)

* High prices as customers often don't have any other options

* Occasionally the company won't deal with me as I'm only ordering 1 or 2 parts at a time, not hundreds

* Proprietary parts requiring complicated installation - unfortunately I can't direct link but have a look at any of the front brace/fork assemblies on http://www.sunparts.us/

* Slow shipping times from the US to Australia, requiring me to plan ahead for any future damage/repairs!

[alexchamberlain]

You need an open source wheelchair.

[bobbles]

Theres a startup idea if I ever heard one