Hi,
I used the Sainsburys tests when I found out I was pregnant, I got a faint line at 10DPO which then got stronger as the days went on.
I have used the Ebay cheapies before, personally I don't like them as they get evaporation lines which lead to confusing results. I've seen this happen with other women on the forum and its so upsetting when someone gets their hopes up and it doesn't come to anything.
I think a test like Sainsburys is far better, I've never had any problems with interpreting the results. They are reasonably priced at 2 for £3.88, which is alot cheaper than the branded ones like clearblue.
Guess its just personal choice really.