I have used many brands over the years, i remember Rush giving you a headache & a sore nose, pass that, i find what is my favorite is Jungle juice black label, it's long lasting without a headache & no sore nose, it gives you the high you need, it's quite potent but no one wants a timid popper under the nose. You need a good deep hit to give you that awesome high you need when taking a BIG cock. That is my all time favorite, i tried the Gold version but that is a little tame compared to Black Label. It's not super easy to find because not many places sell them but if you know where to look there are some good online stores to order from, i use a very reliable company online to deliver mine for a long time now & you can see from there reviews on trust-pilot they are to be trusted too, take a look at :
Poppers-Shop.de - Dein Poppers Online Versand
They use courier to ship so are super reliable too, The reason i leave there website here is so that you guys have a real place to buy from. When you click the link make sure you click the flag for the UK in British Language or you will end up in the German Language version if you click the German Flag.