Question
I have an opportunity to get a Black and Decker cordless push lawn mower (probably model CMM1000 or CMM1200) through a credit card points redemption program.?I would be using this mower just for trimming as I use a rider for our large yard.?I wondered if you had any experience with this model or know much about it.?I understand they are heavier than a gas powered mower, but are they that much heavier that it would be prohibitive to go up moderate hills? It only takes 5-15 minutes to trim, depending what all I do, so a single battery charge would do.

Answer
I have not used either of these particular model rechargeable B&D Lawnmowers (Amazon.com sells the CMM1200 for $399.99, free s/h).  But I can give you the general reputation plus the current Consumer Reports word on it.

I generally avoid rechargeable units for heavy duty work.  I'm all for rechargeable can openers.  Rechargeable toothbrushes.  You should be aware that this model can take 9 hours to recharge.  Then it will only work for around 45 minutes.  So your idea of using it as a trimmer only, for a maximum 15 minutes, is important. And maybe this is a good idea.

But there are issues with rechargeable batteries, and in the case at least of the CM1000, human error is a frequent factor.  You have to charge these correctly, or they will be damaged, perhaps ruined.  Even with the 2 year warranty, repairing any part of a lawnmower is a pain in the neck.

The CMM1200 does make for an exceptionally heavy trimmer.  It weighs 88.2 lbs.  I would find that kind of weight cumbersome to lug around from garage to recharge outlet to the Lawn and back again to the garage.  You also have to make sure you do the recharging right or you'll damage the battery.

For a battery operated mower, these models are impressively strong.  Most people seem to feel they work as well as a gas mower in taller Grass, which is nice.  It also doesn't hurt to have a backup mower when you need one.  Grass keeps growing whether or not you have the means to mow it, and if you know my position on mowing, it is one of those maintenance jobs that matters when it comes to Grass.  A lot.

All this, if you only had to work on flat land.  You are adding the uphill-factor.  More blood sweat and tears on a hot, humid July afternoon.  Remember, this thing weighs just 11.8 lbs short of 100 lbs.  Life is way too hard to have to weigh in just to trim the Grass.  Sorry.  That's my opinion.