I have and carry a P01 and had my gunsmith do a trigger job with CGW parts, 8lb DA, 6.5lb 1/2 cock and 3lb 5oz SA. Shoots better than I do and is an absolute dream. My only real complaint is it seems to need more lube to run than my Glocks did, so add a drop to the slide rails once a month if dry. I'm debating about putting a red dot on but I'm not a good enough shooter to see the improvement so I'm probably getting a MantisX first.
As far as caliber conversion you can get an SP01 barrel and 10x bushing and have the barrel modified and cut to fit or you can get another 75 series upper. If you search there are some good threads on the Original CZ Forum that discuss the topic.