I have 2 road bikes. The primary road bike is fitted with Look Delta pedals, the spare road bike is fitted with semi compatible pedals that are work with delta cleats. My shoes are 4 years old and are on their last legs. Recently I brought a track bike and have taken the compatible pedals and put them on the track bike and therefor need a new pair of pedals for my spare road bike. I also have 2 spare pairs of delta cleats that have never been used.
I thought the solution was to buy another pair of Look pedals and then I discovered that Look has moved to a format called Keo which isn't compatible with Delta and while Delta is still available, I get the impression that that won't be the case in the futre, so if I brought Delta's I would end up with no matching pedals sometime in the future when one of the sets of pedals needed replacing.
So the options I am considering are;
1. Buy Look Delta and worry about compatiblity in the future when something fails.
2. Buy SPD-SL and new shoes, since I'll be needing new shoes shortly anyway. Use the old shoes on the track bike and spare road bike until they suffer death and then replace the pedals on those bikes, or even purchase a second pair of shoes.
I had passing thoughts about speedplay, but the price of converting 3 bikes over in the long term was a little high and I'm not overly concerned about weight, clearence or double sided.
The factors that impact my decision are (in no particular order);
1. How long will Look Delta be available to purchase new.
2. How long will SPD-SL be available to purchase new.
3. How expensive will pedals and cleats be in the future (as distinct from now which I knon).
4. How much better are SPD-SL to walk in in comparision with Look Delta.
5. How expensive will medium quality shoes be in the future.