The Meprolight Night Sights for the HK P30 are true combat sights that offer improved function over the stock ramp sights.  These sights offer two distinct advantages over the stock sights:  1) they have a "hook" on the front edge of the rear sight which allows for one handed slide actuations but retains ease of holstering.  2) They offer near permanent sighting visibility (12 years) in low and no light situations.  The illumination characteristics are exceptional.  By contrast, the stock sights required a charge from a light source before the sights could be visible in low light.  I am extremely happy with the  Meprolight Night Sights.
A note on installation:  Installation of the sights requires either a sight press (this is the best method to keep the sights true) or a drift punch set (preferably nylon tipped or brass to prevent marring).  I had a local HK Armorer install mine for $25 to avoid potentially damaging my P30 or the Tritium tubes on the new Sights.  If you have the right equipment to change them out, it's a fairly easy swap...  but if not, I would strongly suggest budgeting another $25 or so to get a qualified gun smith to set your gun up correctly.  
Pros: Excellent visibility, front "hook" on rear sight for one handed clearing/loading
Cons: none
                    
This review was written in the old system and had content requirements that are different than reviews written today.