Jerry I have them on my 35 and so does Tim Toth he taught me a long time ago how to set the tabs and it makes a huge difference in cruising speed and fuel consumption to trim the boat out right. I know Paul doesn't use his or has them in a fixed position but I wonder how much fuel economy or better speed he could gain if he did use the tabs. I have my motors mounted so far forward in my boat you would think there is no need for any tabs but there is. Tim has the 427's in a 35 Commander and he uses his tabs and his configuration shouldn't be that much different than yours. Another friend has a 41 and he uses his also again a big difference in cruise speed. I adjut mine everytime the boat goes out and retract them when coming in to dock. I really don't know of any boat that doesn't have trim tabs anymore. I personally would opt for the tabs if nothing else they aren't that expensive and the fuel savings could make a huge difference. A set of Boat Levelor Tabs 18 x 9 would only set you back about 350 with shipping that includes everything you need. You may even find them cheaper elsewhere but you can check them out here I have purchased from this company before and have had no problems with them.
http://www.boatfix.com/cart2/Scripts/prodList.asp?idCategory=270