One of the well known seeder is the Jang JP1 a lot of growers from arround the world use these. One’s for the UK come from a French firm http://www.terradonis.com,they do have an agent in the UK details on web site.
Have a look at youtube and put in Jang Seeder lots of videos
Must have missed that request for feedback, sorry.
We imported the Jang in 2008 before it was available in the UK and here is my review. Note some improvements may well have been made to the most recent model.
Pros: Light to carry around; strong with no weak parts; good range of cogs and wheels for different seed spacings seeds and seed sizes; less inclined to clog up in damp soil compared to another seeder we imported at the same time.
Cons: Not suited to stoney soil or heavy clay; needs a fine level seedbed; the brush that stops too many seeds going in to each planting hole is not always effective, resulting in too many seeds in each hole.
Finally if the chain is too loose (I think our’s stretched) the machine can skip holes, resulting in a seed density a low as a 10th of that intended!
There is (or certainly used to be) an AP3 and AP6 with 3 and 6 drills joined together. The machines are (were) available in the USA, with brochures in English, long before they became available in the UK. Another thing to consider is the seed drills that attach behind a 2-wheeled tractor, although I don’t think they are available in the UK.
Thanks everyone for your helpful comments. We have been a little busy with snow and tree planting. It looks like Terradonis. Still open for seeders for our 2 wheel tractor.
Any advice on 2 wheel tractors still welcome.