I actually posted a topic about Oh So a while ago - same with Jameson - he absolutely adores the whole Oh So range!! Infact, he used to go crazy over Hi Life Essentials, but once I gave him the first pouch of Oh So he has a new favorite food! He gets really excited about his meal times, and will always lick his bowl clean.
Jameson was never keen on fishy wet food (tried Hi Life tuna, salmon pate, Feline Fayre etc) and he turned his nose at all of them. Was a bit wary of buying too many boxes of the Oh So Fishy but turned out he goes bonkers over that too. So all good!!! (he loves herring!)
Hi Life Essentials is actually cheaper (£2.88 for 12 x 85g pouches, as opposed to Oh So; £4.19 for 12 x 85g!), and with a higher meat content (50% as opposed to 14%), so when I saw the recent offer in Sainsburys (half price!!) I stocked up and bought enough boxes to last for at least 6 months. Bought all different types: Oh So Fishy, Oh So Meaty in sauce, Oh So Meaty in Jelly and the mixed packet of both Oh So Meaty AND Oh So Fishy.
I still give him Hi Life a couple of times a week. Otherwise he'll get Oh So Fishy for breakfast, and Oh So Meaty for his tea. (all with free flow of PAH premium bisquits)