Hi allergic, I think so. Not a single parent but DH works long shifts at night, out of the house for 16 hours at a time and sleeping the rest. On his days off it was a big help but I was coping alone for the majority of the time.
DCs were 14 and 10 when we got pup, so a bit older than yours. But yours are old enough to be sensible, so that will help.
There were lots of good bits. She was cute beyond belief and very funny. Did lots of adorable things and made us laugh. She was very quick to toilet train in the day, virtually immediately, but took months and months to learn to hang on through the night. She was very quick to learn and would provide any behaviour required if there was a treat at the end.
The bad? Well, she was a mad bundle of energy. She used to have a "mad hour" every evening before bed when she would literally charge round the house without stopping, sending stuff flying in her wake. She would chew anything and everything that looked vaguely chewable. This included socks, toys, food bowls, chair legs and skirting boards. The decorative edging on the top of our stairs she ate right away.
As an adolescent, it got harder. Be prepared for this as it's when most people return their dogs. They lose the cute factor and you suspect you are going to be left with this behaviour for ever. You look at other people's calm dogs and wonder how they do it. At this point she stole food, continued to chew, added fighting our old dog, jumping boisterously at guests and tearing our clothing to her repertoire and generally did nothing we wanted. We went to endless dog classes which taught her how to behave perfectly at dog class. 
She is nearly two now and the glimpses of the wonderful dog she is becoming are turning into long sightings. We took her away for half term and she greeted every stranger by sitting and wagging her tail. She came back to us on walks the minute she was called and didn't once jump at a passer by. She occasionally mistakes a pencil for a stick but otherwise our furniture is safe from her teeth. She can greet the cat without the need to chase him. I love her beyond all measure and have never regretted getting her. She's amazing. 