FWIW - I use the same ones that Dave.David suggested above and have had no trouble scraping in the corners. They are MCL FIXED peg lowering blocks.
NOTE: These blocks still fold just like the stock foot pegs - and that is important. They are inexpensive, easy to mount, nearly invisible and they work like a charm for me.
NOTE: The MCL "Adjustable" peg lowering kit - does NOT fold - and IMHO - that is dangerous.
The enhanced comfort for my poor old knees is WELL WORTH the cost of slowing down a tiny bit the odd time.
The only time I have touched them is when I was in a round-about and I was actually trying to see how far over I could get. It was night but the traffic circle (as they are known here) was well lit, I was alone, there was NO traffic and the road was perfectly clean and dry. I simply went around and around, speeding up a little on each lap until I touched the LH peg. I was going.....well....I was going pretty fast and certainly faster than I would have gone under normal circumstances.
Anyhow - if you've got knee or hip discomfort, these darned things work well - especially in conjunction with the MCL bar riser. Those two items have certainly allowed me to keep riding the ST.
If others don't need them - well, lucky you.
Cheers,
Pete
on safe/quick removal.