Frer is the gold standard in early detection.
IC are best for value. If you're a poas addict like so many of us, stock up on amazon haha.
Cb digi with weeks indicator is best for (obvs) indicating weeks, but also lots of women (me when I was preg for example) use them in early pregnancy to check that hcg levels are not going down.
Any digi is good for if you get line eye! No squinting necessary.