Plastic bottle greenhouses

Has anyone ever built one of those recycled greenhouses? I've downloaded some plans and I'm busy saving bottles... but it would be good to hear anyone's experiences of them.

I put up a new glass greenhouse in the spring - but it's full, so am thinking I could have one greenhouse for iddy biddy seedlings and another one for big plants.

ta

 

Hard to beat a greenhouse with a unique design, only downside is collecting bin bags full of bottles