scrambled I am now a recognised expert at all things to do with pee sticks 
and based on extensive research my recommendation is First Response.
Internet cheapies are great if you are an obsessive tester, you can PIAR every day and then if you see a hint of a line you can then go and buy a proper branded test.
If though you suspect you are updiffed yet have no cheapies go straight for First Response. Clear Blue +/- do seem to leave an evaporation line therefore you'll go mad squinting at it and holding it up to every light in your house wondering if you're preggo or not.
Clear Blue digitals are great for establishing if you are pregnant as it literally spells it out. However, I do not recommend you use these after you have your BFP. You will become obsessed with the conception indicator if it doesn't move along week by week exactly as you've calculated yourself. Loads of threads on here about it. "Clear Blue digi has been stuck at 3 weeks pg for 2 weeks" etc.
First Response don't seem to leave any evaporation lines and are also sensitive. I've not used any Supermarket ones but I've also heard that the Superdrug ones are very good.
Sorry Generic I did giggle a bit imagining you filling your dentist in with all the details