[Chris]

Neat Idea,

We did that exact thing last year and experienced no failures. Its perhaps a little tougher to assemble than a standard gearbox, however we felt it made up for that slight difficulty in great packaging.

My one caution would be to watch which way your bearing flanges face, you want to design it in such a way that a bearing can't fall out and cause a failure.

For Reference here's a picture of ours.