We are currently spending an inordinate amount of time looking into this right now.
There is a fantastic range in portable outboard motor brands to choose from. Significant improvements in materials and build quality in recent times certainly suggest that in 2010 many of the less expensive outboard motor brands are now near on par with the more expensive brands in the critical areas of build quality and reliability.
There are four factors governing our choice of portable outboard motor to power the commemorative Hartley TS21 trailer sailer. Reliability, build quality, cost and suitability. The first two can really only be determined by painstakingly researching real world experiences - not an easy thing when you are looking at the latest outboard motors.
The third factor, cost, doesn't need an explanation from me but the fourth, suitability, relates to us wanting to choose an outboard motor brand that offers a full range of motors that are ideally suited to power all types and sizes of trailable sailing boats.