Great having the 2x10 meter reels that in our case went two directions around the ceiling cornice and met on the other side. So no obvious break in the led spacing which was good as the strips are all visible in our installation. You can join the strips so it’s one continuous 20M strip but the join will cause a ~20 cm gap in the leds.
The reason for only 3 stars is the adhesive and unclear instructions. As someone else mentions these strips have what seems like a plastic backing. That backing is meant to come off but unlike a wax backing its really sticks to the strip. More adhesive comes off and stays on the plastic backing than stays on the leds strips making the leds hard to install. Thankfully there’s double sided foam tape which did come with it. We had to cut and place 1cm tape pieces every 10cms on the strips, in our case it was absolutely necessary to have any chance of sticking. Fingers crossed I hope it survives the 40 degree summer days as it was a pain to get up but worth it in the end.