Personally, having used most every tom mic available, I like the beta 98's better. You do have to be more careful with mic placement though. They are sensitive little buggers with a very hot output. Changing the angle and height of the placement makes a much larger difference than it does with most dynamic tom mics. As far as the little AKG micro's go, I really did not like them much at all. Every once and a while I run into a set of them and try them again thinking that maybe I have changed, but it's always the same. Kind of dull an unflattering.
I sue the Sennheiser 604's alot as well though and find them to be pretty nice. I may not like them as much as the 98's, but I wouldn't lose any sleep over it if I brought my Sennheisers instead of my Shure's. What I don't like about the Sennheisers are the stupid clamps. The clamps have a very weird angle to them that often leaves the mic pretty high up off the tom and can be a real issue if a drummer plays their cymbals fairly low, or has a lot of cymbals on the kit. You can turn the mic around on the clamp and that helps the height issue, but then it limits how far over the drum you can get the mic and the angle in doing so.
I have discovered that in general I am not too picky about what tom and kick mics I sue as long as they are professional mics and not cheapies (i.e. samson, nady etc...). For kicks I own Shure beta 91's and 52's, AKG D112's, Sennheiser 602's, and an EV PL20. For Toms I own Shure beta 98's, beta 56's and
PG 56's, Sennheiser 604's and 421's, and EV 408's (the original ones, not the new ones).
So far my all time favorite tom mics are my EV's. I like them even better than the Sennheiser 421's. On live stages when I use them I out them on the Shure A56D clamps. Those are the same clamps that come with the beta 98's, but instead of a goosneck arm like the 98's have, they have
a solid metal arm with 2 mic threads. This means you could put one clamp inbetween 2 toms and attach 2 mics to it. Also, the shure clamp is capable of a much wider width than the other clamps I have used, and can be adjusted to clamp to cymbal stands with out leaving "claw" or "teeth" marks on them. The shure clamps allow me to place mics at a lower profile than most clamps without sacrificing mic position.
Just my 2 cents