Most people may disagree with me but I speak from 15+ years of experience using aftermarket SFPs with Cisco gear. There's no difference!
Cisco DOES NOT manufacture SFPs, they OEM it from Finisar and possibly others. I've bough SFPs straight from the Finisar factory and they told me Cisco was one of their clients. All they do it put a different branding sticker and sometimes hardcode a vendor ID in it, that's why you get a warning on some Cisco switches.
Buy it from the right manufacturer and it's the same. 10 years ago I used to buy thousands from the source for $20-30/piece for 1G SFPs when Cisco's list on those was $500 to $1000 !!!! At that point throwing in 10% extra was still 10x cheaper!!! And till today, I've NEVER had a single one fail! I still keep a 10 year old finisar SFP in my laptop bag that been abused, and it still works flawlessly!