I'd say it's probably fine for two boys. Boys aren't terribly active, and especially if you have them out a lot they should be fine. But bigger is always better so if you're looking for one you can afford think outside the box. I don't know what you have there, but here we have local websites that sell or auction used pet items. We got a huge four foot
bird cage really cheap off of a website once. All we had to do was add a couple of $2.00 baking sheets as comfort shelves and a couple of $4.00 bird ladders and it was an awesome
rat cage for way less than it would have cost me to actually buy a commercial rat cage that large. Check newspapers and garage sales too.