I was hot to try the Nano Batts until I read a review on Amazon. The guy said that the new batteries will indeed “fit” the current Dewalt 18V cordless tools but because new battery is physically so much smaller than the XRP, it seems to lock in loosely and also leaves the front quarter of the tools base exposed. This could allow dirt and debris to collect and prevents you from being able to stand or balance the tool upright on the battery, like you would sometimes do with the cordless flashlights. I have no doubt that it was more profitable for DeWalt to do what it did, which is to design a whole new tool line around this battery system to take advantage of the smaller size, but it would have been nice if they had taken into account the millions of customers, like me, that already own thousands of dollars worth of their existing product line and would just like to upgrade to the newer battery technology. Maybe Dewalt will release an actual retrofit version for the existing 18V tool line, but I wouldn’t count on it. Milwaukee managed to make their new Lithium battery fit their existing 18V line. Dewalt should be able to do the same.
Black & Decker ... the sponsor of the DeWalt cordless line developed the first cordless tools, at taxpayer expense, for the space program. They then were allowed to make the batteries and chargers 'proprietary,' (meaning no one else could make interchangeable replacements) .... and let the innovation wither on the vine.
I had one of the first "cordless drills," and, despite it's princely price, it was complete junk.
Then, along came Makita. Marketing a line of many different tools, with interchangeable batteries, better chargers, and much better batteries, Makita entered the trades like a whirlwind. They pretty much ruled the roost, up to the day DeWalt (then a new B&D acquisition) exploded on the market.
Makita lost its' lead because it had become complacent. They are still - 15 years later - trying to recover from their loss.
DeWalt seems to have learned all the wrong things from these past experiences. Their quality seems to no longer meet expectations, and there seems to be a certain smugness in their attitude. (At a recent 'Counter Day,' the D-Boys had their fancy trailer, but were nowhere to be found).
IF I am not able to use the new batteries with my older tools - I'll just have to buy new tools. However, when that moment comes, DeWalt will no longer have the "common battery" advantage they now have (on my truck). If I must carry another charger, and set of spares .... they might as well be Makita. Or Milwaukee. Or Ryobi.
I still have 2 9v Makita drills that won't die. One battery is gone but the other 3 still work fairly well. The 1995 vintage one is pretty weak tho. I still use it on my work bench where the charger is handy.