There is one real problem and one potential problem:

The real problem is that the valve stem will be on the inside of the wheel and inaccessible without removing the wheel from the car. It will be a pain in the ass to check your tire air pressure.

The potential problem is that on some three piece wheels, the inner halves are made with a thinner gauge aluminum. I know Simmons were and the brochure for new SSRs say they are. When I was in school, I worked at Epsilon; their rim halves were all the same gauge. The only difference between the inner and outer rim half was the valve stem hole. I don't about the classic Hayashis so you should check...

Well, you could drill a new valve stem hole but I wouldn't (but then again, I am risk adverse almost to the point of paranoia)...

To me it would be too scary to randomly drill a hole in the rim half due to possibly advertently introducing a stress riser. Plus, valve stem holes in spun rims are punched not drilled; drilling again may introduce stress risers. Finally, you will end up with two valve stems. Although, this appears to be the new fad. I saw a picture of a set of wheels (9UL?) on one of the car websites I visit regularly in which the wheels all had two valve stems. I thought they were blems when I first saw the pictures. But, apparently, there are two valve stems so that you can purge any air in teh tire while filling the tire with nitrogen to eliminate all air and get 100% nitrogen. Seems like overkill to me...