I don't know what you are comparing the Picco .26 to. I have a Stock Savage 25 and never ran it against a Picco .26. From what I read, the Picco .26 would walk (maybe run!) away from me.
If you have a .21 and want to upgrade, I would say go for it. If you have a .25 already, the decision may be harder. I am hearing that the Picco is a bear to initially tune, but once it's tuned in it is OK.
This brings me to my next topic, the WASP. If you are interested in the Picco .26 look at the Orion WASP .26 (the price at Tower is great). Some say they are the exact same engine as the Picco .26. Others are saying that they are different. (Can anyone shed some factual light on this?) Across the board, however, WASP owners are saying that they are easier to tune. In comparing the two engines, this may have something to do with the style of carb. The Picco guys say the black carb is easier to tune than the silver (I may have this backwards). I think the WASP only comes with the black - so that MAY be the core issue right there. At any rate, I have my eye on a WASP - once I get my fill of the stock 25 - which is doin the trick for me now.