I bought a trailer for my ds to ride in but his seat doesn't seem very good. It is made out of the same canvas material the trailer is made out of and is held taught by straps. Seems fine in principle but after we have been out and i help him out the seat it is always squashed up and i wonder what on earth his little bum has been resting on for the last hour! The straps are as tight as they can go. I'm looking for another design trailer that has a rigid seat that wont squash up. All of the seats i have seen on ebay are the same design(i think) any ideas on which model to go for?
I have a Burley Cub (google it!). The bottom is basically a plastic shell. We have a double (which you can strap for just one or for two children), but there is now a single available too.
I would highly recommend it. The quality is excellent and here where we live (Germany), it always does extremely well in all aspects (quality, durability, safety, value for money, etc.) of consumer tests.
Good luck. Unfortunately, bike trailers seem to be very expensive all round. I only managed to justify mine by the fact that I didn't have a car and it was our only form of wheeled transport!
Would strapping a car booster seat (or similar) into your current trailer perhaps help solve the problem with it? That might help keep little one stay in place better (and also give him/her a bit of protection from the canvas in case it gets wet).