Maxon Overdrive

i have an 808 and it sounds stellar. i have a ts 7 aswell, and i use my guitarists wylde overdrive. the maxon is my fav out of the bunch and i find myself using it 90% of the time!!! its funny how light it is compared to the other 2 pedals !!!
 
Since we're talking Maxon, can anyone clarify the difference between the Vintage, the 9 Series etc? It seems like they are just repackaging the same pedals except maybe higher grade components for the more expensive pedals? The addition of actual tubes seems like justification enough for a price hike but they only make 2 or 3 tube OD's. I don't know much about them and pedalgeek.com doesn't really say much other than the following...:

'The quintessential <insert pedal type here> pedal - often imitated but never matched. Identical to the original circuit and featuring the <insert rare chip name here> IC chip, the <insert pedal name here> offers <adjectives> similar to a full-up tube amplifier. Incredibly transparent, the <insert pedal name here> responds to individual playing dynamics and lets the true tone of your instrument shine through.'

I just don't understand why an overdrive needs to come in 9 different flavors from the same manufacturer. I will admit though that I have only used three pedals in 10 years and I only kept 2 of them for a week ( Boss DS-1 and GP-20 went right away ). I hear lots of great players talk about their TS-like OD's but I've never had the chance to just plug into one with my gear and see WTF the hype is all about.