1998 Tiara 40 Express opinions?

I am a new member and have been reading your discussions. I've planned on getting involved in boating in Lake Michigan again. I was on the verge of starting by buying a 1999 SeaRay 340 or 370 until I learned in one of your discussions that the waterline can be above the exaust riser causing water to enter the engine and possibly require the engine to be replaced. When I recently confronted the salesman about this he responded that this could happen in the Sea Ray as well as in the Meridan he both recommended. So much for salesmen.

I am starting to look at a 1998 Tiara 40 Express with twin 3208 Cats(which is about where I wanted to be in a couple years). I felt safe in the boat and that it could handle Lake Michigan fishing and cruising. I would get some training so I could handle it.

Does anyone know:

1.) Where I could get performance data(mph,mpg,rpm) on this boat? I've checked sites like boattest.com and there is nothing for this year/model? I don't want to contact Tiara yet since they link me to their dealers and really don't need to hear from any more salesmen.
2.) Any known issues with this model?
3.) Can it slow down to 2mph on one engine for trolling for salmon with out the addition of a trolling valve? I've seen data on their newer models run 4mph at 600rpm. Can trolling valves damage an engine if used properly?
4.) Cummins or Cat? I still have time.
5.) Other comments?

Thanks,

Greg