never tried them with Shimano cleats when I used them BITD.
ti version is lightweight and within weightweenies a common and cheap method to loose weight (used pedals fetch arround € 30 on ebay)
you have to get used to the "feel" when steppin in and out, but once you are in, they are fine.
I would use them mainly for reducing weight on a bike which I use only occasionaly - you cant beat Shimano pedals in terms of comfort and longlastingness
I second your comment on shimano longlastness - even though I roll on Time pedals these days. But the Corretec looks kind of nice. So I will fit them on my Kona that is used only a few times a year (too little frame).
If anybody know if you have to get soecial cleats or they will work with shimano I will still like to hear from you.