My advice is: go to a supermarket. Buy a pack of multi-coloured "snack" peppers - cone shape around 3x10cm (max) for about £7 a kilo.
They are also called "mini sweets" in some shops and "chiquino" in others.
Usually a pack of ~6 costs £1-2. It's worth it...
a) They taste better than most peppers - the orange ones are outstanding, even better than fancy long horn ones.
b) They come true from the seeds.
c) The price of the peppers is high until you realise you have 3 different seed packets there - that would cost you more than £10 from b****y t&m and they'd probably be half the size or less.
d) The plants are in proportion to the fruit and crop well in a 25cm pot and even better in a bigger one.
Cheers