Personally, I feel keeping a decent separation between work and business is a good solid plan. Even if your employer allows you to use your laptop on the job, or they allow you to use their laptop for your personal use, I would say it's not worth the risk involved to take them up on that.
I've had computers freeze up and need a complete operating system reinstall because of a game I was playing. It didn't affect my work the next day, because it was my laptop, not theirs, that had the issue. I had coworkers at my previous jobs who held up projects by weeks because of issues they caused their company laptops with their reckless personal use. It felt unprofessional to me. I would have felt differently about it if our employer wasn't paying us a decent rate, but they were paying us fairly well.
Looking at it from the perspective of looking out for yourself, I've also heard of companies firing people with no notice, and insisting on getting their machine and any backups the person made of it back immediately. In the US, I'd consider this an interesting legal situation I don't know enough about.
But I really don't need to know about them to want to avoid them like the plague. I've known people it happened to, and still couldn't imagine going through that. I wouldn't want to, really. Laptops are relatively cheap these days, if you have a decent job, you can afford to keep your digital work life separate from your digital home life, and I feel it's well worth the cost.
All of this having been said, my personal advice is to take the route of financial prudence and don't spend money before you have it unless you need it. I've put up with hauling significantly heavier computers around to avoid saving money, but I'm not you, so I can't say for certain the 10 pound weight is too much. I can say having a good laptop backpack properly worn using both straps properly cinched up and fastened together may add a few extra pounds on top of that, but make it seem like the whole thing is only a couple of pounds.
On another note, last I checked, there were portable bluetooth keyboards that you could get that would sync with an iPad, and let you do programming on the go. I don't know a lot of details about them, except that they exist, and iPads probably still support them. Google gave 'ipad bluetooth keyboard' as a suggestion at just 'ipad blu', and found about 70 million hits. Just saying, so you know.