Sorry to have kept you on tenterhooks, UrbanManc!
I've owned by EBC trailer for about a year. It's very closely based on the Bob Yak, but by no means identical.
Until last month, I'd only ever used it for short trips - camping, picnics and beach barbecues. Our trip to Wales was the first time I'd used it on a proper tour.
The trailer has a frame of square-section steel tube which can be flat-packed when not in use. A single rear wheel attaches via a quick release. On the bike, a replacement rear quick-release skewer has wide stubs that receive the hooks which extend from the main trailer body. A nearly-waterproof fitted dry(ish) bag fits into the trailer and a flag completes the package.
We traveled from Brighton to Llanelli by train, which was the first challenge for the trailer. Negotiating our way onto trains was made easier by co-operative rail staff, but was by no means easy. Our journey involved two changes of train. The first platform change (at Fratton) forced me to separate the trailer and carry it separately up to staircases - not fun.
Thankfully, the passenger lifts at Cardiff are large enough to receive a bike and trailer without having to disconnect. Our final train was a very crowded two-car rural affair. Our fellow passengers were very understanding and helped a nightmare become tolerable.
Once in Wales, we hitched up and set off, me towing the heavily packed trailer behind a hardtail cross-country race mountain bike.
I won't deny the trailer takes a little getting used to, but compared to the two-wheeled trailers I've used, it's fantastic. The trailer's wheel tracks the bike's rear wheel almost exactly, making it a good choice for off-road riding. Climbing hills is no more difficult than doing so with chunky panniers - maybe even easier. And fast cornering is absolutely fine - really confidence-inspiring. The only times I feel uneasy with the trailer are during fast lane-changes on quick roads. A simple sideways movement between lanes can sometimes lead to a kind of snaking sensation. Not enough to cause a real problem, but worth being aware of.
And so we continued for 250km - mostly on narrow country lanes, with a few off-road sections and some occasional larger roads. The trailer behaved very well, and its load continued to grow as items of my girlfriend's kit began to migrate mysteriously into my trailer bag.
After a particularly difficult off-road section we suffered a spate of punctures, but it would be unfair to blame this on the trailer's design - just one of those things.
The large orange bag, though it looks waterproof, is not, and I learnt to keep my clothes in plastic bags while riding through the wet Welsh weather. This may have been less of a problem had I not omitted to add the mudguard that came with the trailer. And if the end of the world had not fallen from the sky as we rode back through Llanelli on day 7...
The journey home featured larger, less crowded trains, so was less stressful. We arrived back into London Paddington late at night and opted to ride to Waterloo and take one last train to Putney, our final destination.
It was as we left Putney station, with only a mile left to ride, that the trailer developed the only real issue of the trip. After carrying it up the stairs, I couldn't seem to reconnect the hooks to the stubs mounted on the bike. After fiddling with it for a while, I had to turn the trailer upside down to locate the problem.
The 'hooks' which locate onto the bike's axle stubs are in fact each made from two steel plates with a space between them. This gap accommodates a smaller hook, which rotates with the aid of a small fiddly button in order to lock the trailer to the bike. One of the outer steel plates had bent inward a small amount, preventing the inner hook from rotating forward and performing its purpose. The problem was cured by jamming a large screwdriver into the gap and prising the plates apart.
To be fair, this problem was probably the result of my clumsy attachment and re-attachment technique, dropping the trailer into concrete floors while steadying my bike with my spare hand. If I'd been more careful or more gentle, I'm sure this minor damage wouldn't have happened.
I'm looking forward to using the trailer again, but will take more care with the attachment mechanism, and might even fit the mudguard next time.