Do you have inspections? If so do you have access to their guidelines?
Do you hit potholes hard enough to bottom out? If so I'd say lowering by any means is not for you. If not then I wouldn't worry about it.
What we need is for someone to explain WHY these would destroy a suspension.
Of course there can be effects from excess lowering no matter what method you choose.
Frinstance, really slamming it but not re-adjusting camber will cause at a minimum faster tire wear I'd think.
And slamming it and then slamming into potholes will of course jar everything.
It is possible for one of those bolts to break I spose if they aren't good bolts.
It is possible for the clamp to cut into or nick the spring I suppose? Maybe? Maybe not? We don't want any substantial nicks on springs. I've seen some pansies go ape over nicked paint. Well the paint on all my vehicles springs is hanging there in shards due to being in the rust belt and maybe 50 years from now I'll notice a bad effect from it.