I've worn my BAHA Intenso (a little larger and more powerful than the Divino model since the hearing in my good ear isn't absolutely perfect) since June 2008 and am quite happy with it. I had the titanium implant "installed" at the same time as my AN surgery (translab procedure), so I was sound asleep; folks who have it done later say that it's not a big deal -- comparable to a dental procedure -- and most seem to have it done under local anesthesia, which, in my mind at least, seems to confirm the "not a big deal" consensus.
BAHAs are not considered to be hearing aids, so hopefully your insurance will cover it. Be forewarned, however, that many insurance companies routinely deny coverage at the first request so getting approval can sometimes be a lengthy procedure.
The helmet issue could be a bit tricky, and I think that many BAHA wearers just wouldn't wear them (the BAHA, not the helmet!) in cases like this. I have personally not worn a safety helmet with my BAHA, but I haven't been in a situation where I've needed one .... so hopefully someone with personal experience will give you a better answer.
The processor (the part that attaches to the titanium implant) is very discrete. I wear my hair pretty short and tucked behind my ears and have never had a problem. If you're getting a Divino it will be even easier to "conceal." The processors come in several colors, so you can get one as close to your hair color as possible.
I know that there are several Forum members who are quite happy with their Transears and I'm sure that they, as well as other BAHA users, will chime in as well.
Best wishes as you reach a decision!
Catherine (JerseyGirl 2)