I'd be more concerned about parts and service than stability. Terex doesn't make any of the boom trucks any more and you will be out of luck for any parts or support. I never had good luck getting anything from them when they were still making equipment here. Nor did they have a great reputation.
I think the angled front outriggers would be awkward in some tight spots because you can't just slide the outrigger between two obstructions, you would need a lot more room for extension.
The chart for that crane shows a big deduct working over the front, and when you back into a yard/driveway, you're going to lose a lot of radius because of the bed/deck length behind you. A rear mount gets you a lot closer to your work.
All that said, I've never run a terex 28106 personally, and they might be the best thing since sliced bread. But if I was buying a boom truck- it would be a national or a manitex.