I have 2 from Rosemania that I have not had any trouble with - so far. One is the small Duromax (Flo Pro) 1.3 gallon sprayer... http://rosemania.com/shopsite_sc/store/html/product490.html sells for $89.95. I like it because it has a shoulder strap and I can zip around and quickly spray all of my roses in about 30 minutes. The other one is the Spotshot 7 gallon sprayer that you already mentioned earlier.... http://rosemania.com/shopsite_sc/store/html/product93.html I have not had any problems with it either. But it IS rather pricey - $400. It is harder for me to maneuver around the garden when it is full - even though it has wheels. I mainly use it to apply the Bayer All-in-One soil drench. It makes applying that so much easier. I use it without the spray nozzle. Here is a link that might be useful: Duromax (Flo Pro) 1.3 Gallon Battery Powered Sprayer

There really is no way of telling. It depends on the type of battery (NiMH, lithium ion, etc.), how many discharge/recharge cycles the battery has gone through, whether the device is plugged in most of the time, storage conditions,.... Sorry this isn't much of a help. But it's kind of like asking how many licks there are to a Tootsie Pop. :-)

From CPSC.gov: "Name of Product: Battery packs used with Polaroid-brand portable DVD players Units: About 165,000 Manufacturer/Importer: Petters Consumer Brands LLC, of Minnetonka, Minn. Hazard: The battery can overheat and melt the plastic case while recharging, posing a fire and burn hazard to consumers. Incidents/Injuries: Petters Consumer Brands has received eight reports of batteries overheating, melting the plastic case, or units smoking during the recharging process. No injuries have been reported. Description: The recall involves external battery packs used with the Polaroid-brand portable DVD players in 7-inch and 8-inch screen sizes. The 7-inch DVD player has model number PDV-0700 and 8-inch player has a model number of PDV-0800. The players and battery packs are silver in color. The battery packs attach to the bottom of the DVD player. Sold at: Various electronics and department stores nationwide from May 2003 through March 2004 for between $150 and $350. Manufactured in: China Remedy: Consumers should stop using and stop recharging the battery packs immediately and contact Petters Consumer Brands for a free replacement battery pack. Consumers can continue using the portable DVD player without the battery, by detaching it from the unit, and plugging in the DC Cord or the AC Power Adapter. Consumer Contact: Consumers should contact Petters Consumer Brands toll-free at (866) 866-6292 anytime to arrange for a replacement battery pack, or visit the companyÂs Web site at www.Polaroid.com to sign up for the recall." The complete article, with serial numbers and pictures, is linked below... TJ Here is a link that might be useful: CPSC.gov / CPSC, Petters Consumer Brands LLC Announce Recall of Batteries Found In Polaroid Portable DVD Players

As with cordless power tools, you're paying for the convenience of not having to deal with a cord (or air hose). Of course a big battery is going to add considerably to weight and bulk. If you have a decent compressor, then you're probably going to save some money going with air tools, not to mention they'll be more compact. Torque should be torque but as you've learned, batteries die with use. Lithium is the way to go, along with high capacity batteries (measured in amp hours, more is better). Milwaukee has a 3/4" impact that puts out a "maximum" of 750 ft-lbs. of torque tightening and 1,200 loosening. The kit will set you back about $500. ;-) And they will be bringing out a 9 amp hour battery this fall. That's a big battery... As I'm sure you know, there are many grades (and price points) with tools. A few years back I used a spiffy, new Snap-On impact and it was pretty sweet. More than the average shade tree mechanic should probably spend though.