Any tips for good serum

[Celia1978]

My not-very-ambitious resolution for 2014 is to start using serum regularly - but which one? If you love (or hate) any you've tried, please let me know.
Have experimented with Advanced Night Repair and Lancôme Genifique in the past but neither seemed to suit my skin and caused breakouts. Skin is mid-30s, fair, bit dry, bit sensitive but mostly fairly well behaved.
Any thoughts?

I really like Vichy Lift Aktiv. I think their sensitive skin range is called Aqualia and they'll do a serum within that range I'd think

The Boots Time Delay ones get good reviews & are not expensive.

I've recently tried a sample tube of Vichy idelaia which I really liked! to the extent that when my genefique runs out I'll be buying some.

This is the most lovely thing I've ever put on my face and smells divine :) www.thebodyshop.co.uk/shop-by-range/vitamin-c/vitamin-c-skin-reviver.aspx

When do you use serum? What are the benefits?

Thank you for your advice!

Jjcrackers, as I understand it serum is used between cleanser and moisturiser - I think it's meant to be a really intensive dose of skincare.

Origins Plantscriptions. A tube lasts ages and I can really tell the difference - been using it a year now - my skin looks healthier and the very faint fine lines that were appearing have been been held at bay so far...

I use this one.
It has good reviews, I like the feel of it and it is often half price

The boots one just mentioned looks good. I tend to chop and change, I've just finished the Clarins dual one, now finishing Elemis pro radiance then I feel a trip to Boots coming on!