I like clipless pedals and have been using since 1989
I like the spd-sl but also use spd for commuting or when I need to use a shoe I can walk in a bit (rainy days from bike locker at work to the lobby)
SPD is in general a little easier to get in an out of, but seems a bit less efficient, so depending on your usage spd may be a consideration
your shoes should be able to handle spd-sl or spd
__________________
Life is too short not to ride the best bike you have, as much as you can
(looking for Torpado Super light frame/fork or for Raleigh International frame fork 58cm)