You get a nicer house with a butler if you blow up the bomb tho soo..yea
That is correct, but I find both ones to be far too tiny for my purposes.
I do find saving Megaton seems to be more beneficial, though, since you can still enter Tennpenny Tower even if you don't destroy Megaton, therefore, you lose one town if you destroy Megaton, not that it makes too much difference, since you can avoid losing the quests in Megaton if you do them before blowing it up, the only merchant who is really useful in the town won't die anyway, and the unique items Lucas Simms has can be acquired before blowing it up, when I did do so, I actually killed him before going to Tennpenny Tower just so I could take his coat and hat and I could get the key to his house so I could get the Bobblehead. You also can no longer sell scrap metal to Walter, which is not a huge problem, since you can sell it elsewhere to, and you'll have more bottle caps than you can hope to use with our without him anyway. In the end, saving Megaton is, I would say, beneficial, but not enough so to give you a reason to choose that over blowing the town up if the latter is what you really want to do.
As to the items you get in your house, I have to agree the infirmary and lab are the best, the infirmary mostly for curing radiation only, since you can heal wounds by sleeping for an hour in your bed too, when I had the Tennpenny suite, I also found it helpful to buy a workbench there, as I don't recall there being any in the Tower otherwise, Moira has one in Megaton, so it wouldn't be needed there.