I have a little guy, well he's growing, so not as little as he used to be. I have to be honest, when I bought my first suvattii, I wasn't all that keen on them. I thought they were ugly and I wanted that cute puffer look that GSP's have. However, I have to say that I am now very fond of the suvattii.
As Troender says, they are not at all active. My "Fred" stays buried most of the time or hiding in his PVC tube, but he knows when it's meal time and he shoots up the surface as quick as lightning. Fred is really good about taking all different types of foods, unlike the other suvattii that I've had, which I am glad of. When I got Fred, back in November, he was tiny, but now he's getting much bigger and turning into a lovely little puffer.
I have been bitten by a suvattii (although not by Fred), I was putting a piece of bogwood down into the tank, the suvattii shot up so quick I didn't even see it until I felt the pain in my finger, and seen the little suvattii retreating back to his hiding place. I'm sure the bite was confusion, because thinking about it, my finger going into the water probably resembled a piece of shrimp. I definitely would give a suvattii respect when hands are in the water, and that's not to infer that they are vicious -- but they are quick and if they aren't sure what your hands or fingers are, they might just have a "taste".
Again, as Troender says, they aren't very active and if that's what you want in a puffer, then the suvattii definitely isn't for you, but they are interesting. I was successful at keeping 3 very young, very small suvattii with a Palembang that was also very young and very small. They lived together until I had a spate of internal parasites and didn't know much about them at the time and lost them all.
I now have 2 Palembangs and my suvattii Fred, but I don't think I will try keeping them all together this time around, as I think they are past the age of acceptance of a tankmate.